Veterinary

Have you ever thought about applying a transdermal preparation to the inside of an animal’s ear or another hairless area as an alternate route of systemic administration? It’s quick and easy, and many medications are compatible with transdermal bases. Transdermal delivery is particularly useful for animals who should not be stressed due to cardiovascular or hypertensive illness. Also, it is appreciated by owners who no longer have to deal with an animal who resists being medicated, and the resulting scratches! We can also prepare topical medications for application at the site of inflammation or infection.

Metronidazole

Metronidazole is effective against a variety of obligate anaerobic bacteria as well as anaerobic protozoa such as Giardia and Trichomonas. “Various salts of metronidazole with improved palatability are now available for veterinary patients… Cats and birds accept the benzoate salt much more willingly than they accept metronidazole HCl and do not seem to be stressed by its administration.”

Compendium Dec. 2000: 22(12); pp. 1104, 1105, 1107, 1130. .

Esophageal Strictures Secondary to Administration of Doxycycline Tablets

“The most common causes of esophageal strictures in dogs and cats are gastroesophageal reflux during anesthesia, persistent vomiting, or ingestion of foreign bodies or caustic agents. In humans, esophageal retention of oral medication is a common cause of severe esophagitis. Of the medications proven to lead to esophageal ulceration, doxycycline is most often implicated. It has been suggested that pill-induced esophagitis also could occur in small animals…” Drug-induced esophageal ulceration usually occurs when tablets are taken with little or no water and adhere to the esophageal mucosa. Once this occurs, flushing with large quantities of liquid fails to wash the medication into the stomach. Melendez et al. of Colorado State University College of Veterinary Medicine report on three cases of presumptive doxycycline-induced esophagitis in cats, with resultant stricture formation. All cats had been administered fractions of doxycycline tablets one to three weeks before presenting with a chief complaint of regurgitation. “Two of the cases developed regurgitation within 7 days after initiation of therapy with doxycycline. One cat, which was treated while at an animal shelter, was noted to be regurgitating the day that it was adopted, approximately 2 weeks after being treated with doxycycline. No other cause of esophageal stricture formation could be identified.” If a pet that has received a doxycycline tablet shows sign of esophagitis (dysphagia, excessive salivation, inappetence, and regurgitation), the doxycycline tablets should be discontinued. Suggested therapy for esophagitis includes sucralfate slurries, a prokinetic agent (i.e. cisapride) to increase lower esophageal sphincter tone, and anti-inflammatory doses of glucocorticoids to prevent stricture formation.

Feline Practice 28:2; 10-12 (Mar/Apr 2000). .

Doxycycline can be compounded as a stable flavored liquid preparation or other palatable dosage form to meet the specific needs of each animal and owner.

Oral Itraconazole for Therapy of Dermatophytosis Caused by Microsporum canis

Itraconazole could be an effective alternative to griseofulvin that has toxic effects (particularly in puppies based on this author’s experience) and frequent therapeutic relapses. Itraconazole has also been used to successfully treat M. canis infection of cats and guinea pigs.

J Am Vet Med Assoc 1998;213:993-995. .

Chloramphenicol Suspension for Birds & Small Animals

Antibiotic Treats for Feline Abscess

Intranasal Clotrimazole for Treatment of Nasal Aspergillosis in Dogs

“Treatment of nasal aspergillosis with systemic antifungal medications, such as thiabendazole, ketoconazole, and fluconazole, has been disappointing because the response rate is only 43 to 60%. Response to oral administration of itraconazole has been approximately 60 to 70%… Topical administration of the imidazoles, enilconazole, and clotrimazole is more effective than orally administered antifungal medications.”

Topical administration of clotrimazole resulted in resolution of clinical disease in 65% of dogs after 1 treatment and 87% of dogs after one or more treatments. Topical administration of clotrimazole, using either technique, was an effective treatment for nasal aspergillosis in dogs. Use of non-invasive intranasal infusion of clotrimazole eliminated the need for surgical trephination of frontal sinuses in many dogs and was associated with fewer complications. Nasal discharge ceased in most dogs 2 weeks after topical treatment, and the authors now recommend re-treatment with clotrimazole if nasal discharge has not improved 2 weeks after treatment.

J Am Vet Med Assoc. 1998 Aug 15;213(4):501-6.. Comparison of topical administration of clotrimazole through surgically placed versus nonsurgically placed catheters for treatment of nasal aspergillosis in dogs: 60 cases (1990-1996)..

J Am Anim Hosp Assoc. 1998 Nov-Dec;34(6):487-92.. Management of nasal aspergillosis in a dog with a single, noninvasive intranasal infusion of clotrimazole..

Azithromycin

Azithromycin is a form of erythromycin with improved action against gram-negative organisms, resistance to acid degradation, improved tissue penetration, and a prolonged elimination half-life. Azithromycin shows potential for use in veterinary medicine, particularly in cats and certain avian and exotic species.

Compendium of Continuing Education 23:3 (March 2001), pp. 242-7. .

Azithromycin for R. equi Infections in Foals

On the basis of pharmacokinetic values, minimum inhibitory concentrations of R. equi isolates, and drug concentrations in pulmonary epithelial lining fluid (PELF) and bronchoalveolar cells, a single daily oral dose of 10 mg/kg may be appropriate for treatment of R. equi infections in foals. Persistence of high azithromycin concentrations in PELF and bronchoalveolar cells 48 hours after discontinuation of administration suggests that after 5 daily doses, oral administration at 48-hour intervals may be adequate.

Am J Vet Res. 2001 Dec;62(12):1870-5.. Pharmacokinetics of azithromycin and concentration in body fluids and bronchoalveolar cells in foals..

Itraconazole/DMSO for Fungal Keratitis in Horses

Fungal keratitis is a serious complication of trauma to the eye. Approximately one-half of the cases of fungal infections have involved the use of eye ointments containing corticosteroids after trauma to the globe of the eye.

“Itraconazole is a third generation triazole that has superior penetration properties and a wide spectrum of activity. A 1% solution of itraconazole in a 30% DMSO and petroleum base has been shown to reach high concentrations within the stroma of the cornea when administered every 4 to 6 hours. In general, every 6 hours is suitable for all but Fusarium sp which requires every 4 hour administration.”

Disease which is rapidly ulcerating “should also receive treatment that helps block the enzymes (collagenase) responsible for ulceration. A 5% acetylcysteine solution and autologous serum in which 4 mg/ml of EDTA has been added has been recommended. These need to be instilled hourly for best effect. The antimicrobial can be added to the serum.”

Idoxuridine Ophthalmic Drops for Cats

The ocular signs of feline herpesvirus I (FHV-1) infection include bilateral conjunctivitis, serous ocular discharge which may become mucoid or mucopurulent, and blepharospasm. If corneal involvement is present, topical antivirals are prescribed. Research indicates that idoxuridine is effective against FHV-1. Prolonged contact with the infected tissue is required. The 0.1% solution must be applied five times daily. Previously marketed as Stoxil®, the ophthalmic solution is not commercially available at this time.

Feline Ocular Toxoplasmosis

Transdermal Treatment for Aggressive Cat

Amitriptyline for Behavioral and Urinary Disorders

Amitriptyline hydrochloride is one of the most widely used tricyclic antidepressants (TCAs) in companion animal behavioral medicine, exerting antihistaminic, anti-inflammatory, analgesic, and antidepressant effects. Amitriptyline increases synaptic activity of serotonin and norepinephrine, has significant central and peripheral anticholinergic activity, and stimulates beta-adrenergic receptors in smooth muscle (e.g. the bladder), causing a decrease in smooth muscle excitability and a subsequent increase in bladder capacity and storage.

Naltrexone for Self-Mutilating Behavior

Canine Acral Lick Dermatitis

Involves excessive licking of the paws or flank, even to the point of self-mutilation, and can produce ulcerations and infections that require medical treatment. Based on patterns of behavior and response to medication, veterinary scientists propose that canine acral lick dermatitis, also known as canine compulsive disorder (CCD), is an animal model of human obsessive-compulsive disorder. A randomized, placebo-controlled, double-blind crossover clinical study evaluated the efficacy of the medication clomipramine for treatment of CCD. Fifty one dogs with CCD were given clomipramine 3 mg/kg [1.3 mg/lb] of body weight orally every 12 hours for 4 weeks and then placebo for 4 weeks. While drug therapy can be helpful, therapy may need to include behavior modification to optimally manage CCD.

J Am Vet Med Assoc. 1998 Dec 15;213(12):1760-6.. Efficacy of clomipramine in the treatment of canine compulsive disorder..

Arch Gen Psychiatry. 1992 Jul;49(7):517-21.. Drug treatment of canine acral lick. An animal model of obsessive-compulsive disorder..

Fluoxetine for Refractory Owner-Directed Dominance Aggression

Evidence suggests that social dominance aggression may be modulated by serotonergic mechanisms. Fluoxetine (Prozac®), a specific inhibitor of serotonin reuptake, is a popular human antidepressant which has been used successfully to decrease social aggression in dogs and monkeys.

J Am Vet Med Assoc. 1996 Nov 1;209(9):1585-7.. Use of fluoxetine to treat dominance aggression in dogs..

Fluoxetine for Urine Spraying in Cats

Administration of fluoxetine hydrochloride for treatment of urine spraying in cats can be expected to considerably reduce the rate of urine marking. Pryor et al. recommend that most cats should be treated more than eight weeks before treatment is withdrawn. Cats that vertically marked a mean of > or = 3 times per week were treated for 8 weeks with fluoxetine (1mg/kg PO daily- dosage individualized for each cat by a compounding pharmacy) or fish-flavored liquid placebo. When treatment was discontinued after 8 weeks, the spraying rate of cats that had received treatment varied. The main adverse reaction to the drug was a reduction in food intake, which was observed in 4 of 9 treated cats.

J Am Vet Med Assoc. 2001 Dec 1;219(11):1557-61.. Effects of a selective serotonin reuptake inhibitor on urine spraying behavior in cats..

Inappropriate Elimination in Cats: Fluorescein to Find the Culprit

In a multi-cat household, it is important to determine which cat is inappropriately eliminating so that the proper intervention can be made. Even if one cat is observed marking or urinating outside the box, it does not rule out the possibility that other cats are also behaving inappropriately. When it is necessary to identify which cat in a multi-cat household is spraying or inappropriately eliminating, fluorescein can be orally administered once daily in the evening with food for three days. That cat’s urine will fluoresce under ultraviolet light for approximately 24 hours. To detect urine containing the fluorescein indicator, the client needs to scan the household with a commercial black light or black light purchased from a novelty store. Although urine will commonly glow, fluorescein treated urine fluoresces a characteristic bright yellow. Caution clients that they may reveal previously undiscovered sites of elimination; advise them not to become alarmed or angry. By administering the dye to different cats at two day intervals, the culprit can be identified.

Pharmacological support for urine spraying or marking is usually needed only for cases with underlying anxiety or problems with social interactions between cats (clomipramine), or for cats with interstitial cystitis (amitriptyline, doxepin). Administration of fluoxetine hydrochloride for treatment of urine spraying in cats may also considerably reduce the rate of urine marking.

Cyproheptadine to Control Urine Spraying and as an Antipruritic in Cats

A 10-year-old castrated male domestic cat was admitted to the hospital at the School of Veterinary Medicine, Tufts University. A diagnosis of territorial urine marking was made. Treatment included behavior modification and the administration of cyproheptadine, which resulted in the immediate arrest of undesirable urine marking. Cyproheptadine administration was adjusted to determine the lowest dosage that effectively maintained the cat’s consistent use of the litter box. It was recommended to continue cyproheptadine administration for at least 1 year before any attempt to withdraw its use. Another study recommended a dose of 2 mg, p.o., every 12 hours. This antihistamine, also prescribed for its appetite stimulant effects in cats, has antiandrogenic effects in other species.

J Am Vet Med Assoc. 1999 Aug 15;215(4):501-2, 482.. Use of cyproheptadine to control urine spraying in a castrated male domestic cat..

J Am Vet Med Assoc. 1999 Feb 1;214(3):369-71, 351-2.. Use of cyproheptadine to control urine spraying and masturbation in a cat..

Cyproheptadine hydrochloride was administered to 20 presumed or proven allergic cats to determine its efficacy in controlling pruritus. Each cat received 2 mg, orally, every 12 hours. The pruritus was satisfactorily controlled in 9 cats. Side effects were seen in 8 cats, and included polyphagia, sedation, vocalization, affectionate behavior, and vomiting.

Can Vet J. 1998 Oct;39(10):634-7.. Observations on the use of cyproheptadine hydrochloride as an antipruritic agent in allergic cats..

Clomipramine for Feline Anxiety

A study of 11 cats assessed the clinical response to a treatment regimen that included clomipramine and behavior modification in cats diagnosed with anxiety-related or obsessive-compulsive disorders. Presenting signs were urine spraying in seven cases, overgrooming in three and excessive vocalization in one. Clomipramine was administered orally once daily, with a mean starting dose of 0.4 mg/kg. If necessary, the dose was adjusted according to the clinical response of each cat. The average maintenance dosage was 0.3 mg/kg once daily. The researchers concluded that clomipramine was effective in controlling the signs of anxiety-related and obsessive-compulsive disorders in 10 of 10 assessable cases when used in combination with behavior modification, and the drug was well tolerated.

Aust Vet J. 1998 May;76(5):317-21.. Use of clomipramine in the treatment of anxiety-related and obsessive-compulsive disorders in cats..

Selegiline

is a monoamine oxidase (MAO) inhibitor indicated for use in dogs to control signs associated with canine cognitive dysfunction syndrome and uncomplicated pituitary-dependent hyperadrenocorticism (PDH). Studies suggest that selegiline may enhance survival rates. The recommended dose for cognitive dysfunction is 0.5 to 1 mg/kg, and for PDH is 1 mg/kg, orally each morning. If no improvement is seen after 2 months, the dose can be increased to the maximum of 2mg/kg/day. If there is no clinical improvement after 1 month at 2mg/kg/day, alternative therapy or further evaluation should be considered. “Overall, selegiline is well tolerated… Gastrointestinal disturbances, particularly vomiting and diarrhea, are the most common side effects reported. Diarrhea may resolve when the drug is discontinued or the dose decreased. Other adverse effects include hyperactivity, agitation, restlessness, and insomnia. A dose reduction or discontinuation of therapy also resolves these problems.”

Compendium March 2000; 22(3):204-5. .

Enalapril for Cardiomyopathy and CHF

“Enalapril maleate is an angiotensin-converting enzyme (ACE) inhibitor labeled to treat mild to severe heart failure in dogs.” Research has shown that enalapril in combination with diuretics – with or without digitalis glycosides – “produces statistically significant clinical improvement in dogs with advanced heart failure due to mitral regurgitation or dilated cardiomyopathy” and has demonstrated “beneficial hemodynamic and clinical effects of adding enalapril to conventional therapy for dogs with CHF… Dogs treated with enalapril and conventional CHF therapy survived two times as long as did those receiving standard therapy alone.”

Enalapril has also “been effective in treating cardiomyopathy and CHF in cats and ferrets, and its effects on blood pressure in horses and camels have been studied.” Because enalapril is a prodrug and can not be converted to its active form enalaprilat in patients with severe liver dysfunction, captopril or lisinopril might be a better choice in those patients. Renal function should be checked before starting enalapril therapy and at least every two months thereafter. The most common side effects are gastrointestinal, but there have been reports of enalapril-induced cough in dogs and a bird. Hypotension is a major concern if overdose occurs. NSAIDs, including aspirin, may reduce enalapril’s effect. The injectable form (enalaprilat) should not be given orally because it is very poorly absorbed.

“The recommended dose for enalapril in dogs is 0.5 mg/kg orally every 12 to 24 hours. The dose for cats is 0.25 to 0.5 mg/kg orally every 12 to 24 hours.”

Compendium, Dec. 1999. .

Amlodipine to Treat Feline Systemic Hypertension

Amlodipine, a calcium channel blocker, has an antihypertensive effect in cats with coexistent systemic hypertension and renal insufficiency. Its use may improve the prognosis for cats with systemic hypertension by decreasing the risk of ocular injury or neurologic complications induced by high blood pressure (BP). In a retrospective study, medical records from 69 cats with systemic hypertension and hypertensive retinopathy were reviewed. 68.1% of the cats were referred because of vision loss; retinal detachment, hemorrhage, edema, and degeneration were common findings. Amlodipine decreased BP in 31 of 32 cats and improved ocular signs in 18 of 26 cats. Primary hypertension in cats may be more common than currently recognized.

In a study at the Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, amlodipine was shown to be a safe and effective once-daily antihypertensive agent when administered to cats at a dosage of 0.18 +/- 0.03 mg/kg daily as monotherapy. Researchers at the Department of Medical Sciences, University of Wisconsin-Madison, administered amlodipine at an oral daily dosage of 0.625 mg per cat (range = 0.08 to 0.23 mg/kg body weight). Average indirect systolic blood pressure measurements in those 12 cases decreased significantly from 198 to 155 mmHg during amlodipine treatment. Significant changes in body weight and serum creatinine and potassium concentrations were not detected.

Relationship between ocular lesions and hypertension

Retinal lesions, caused predominantly by choroidal injury, are common in cats with hypertension. Hypertension should be considered in older cats with acute onset of blindness; retinal edema, hemorrhage, or detachment; cardiac disease; or neurologic abnormalities. Cats with hypertension-induced ocular disease should be evaluated for renal failure, hyperthyroidism, diabetes mellitus, and cardiac abnormalities. Blood pressure measurements and funduscopic evaluations should be performed routinely in cats at risk for hypertension (preexisting renal disease, hyperthyroidism, and age > 10 years).

Am J Vet Res. 2002 Jun;63(6):833-9.. Effects of the calcium channel antagonist amlodipine in cats with surgically induced hypertensive renal insufficiency..

J Am Vet Med Assoc. 2000 Sep 1;217(5):695-702.. Ocular lesions associated with systemic hypertension in cats: 69 cases (1985-1998)..

J Vet Intern Med. 1998 May-Jun;12(3):157-62.. Amlodipine: a randomized, blinded clinical trial in 9 cats with systemic hypertension..

J Am Anim Hosp Assoc. 1997 May-Jun;33(3):226-34.. Treatment of systemic hypertension in cats with amlodipine besylate..

Alternative Therapies for Atopy

Dogs with atopic dermatitis (AD) often have concurrent allergies and are prone to relapsing skin and ear infections, which significantly contribute to their discomfort level. Much research has been done in recent years to identify effective and safe alternative treatments. Percutaneous absorption of allergens may be the most relevant route of exposure in dogs. Topical therapy may reduce the amount of allergen absorption through the skin. Several preparations, including glucocorticoids and anesthetics, can be used to reduce pruritus and provide analgesia.

Cyclosporine, misoprostol, pentoxifylline, and various antihistamines have been effective.

Compendium 2001 May 23(5):454-60. .

Tetracycline/Niacinamide for Dermatology

The combination of tetracycline and niacinamide is being used for a continually expanding list of dermatologic disorders thought to be of immune-mediated origin. Diseases that may be controlled with this combination include discoid lupus erythematosus, pemphigus erythematosus, vesicular cutaneous lupus erythematosus (idiopathic ulcerative dermatosis) in Collies and Shetland Sheepdogs, pemphigus foliaceus, lupoid onychodystrophy, metatarsal fistulae in German Shepherds, sterile panniculitis, sterile granulomatous/pyogranulomatous dermatitis, vasculitis, cutaneous histiocytosis, idiopathic lymphocytic/plasmacytic ear margin dermatitis, and nodular granulomatous episcleral keratitis.

The Capsule Report (Small Animal/Exotic Edition) 21:9, December 2002.. Reporting on Proceedings of the Friskies Pet Care Symposium 10:01.

J Am Anim Hosp Assoc. 1997 Nov-Dec;33(6):540-3.. Tetracycline and niacinamide for the treatment of sterile pyogranuloma/granuloma syndrome in a dog..

J Am Vet Med Assoc. 1992 May 15;200(10):1497-500.. Use of tetracycline and niacinamide for treatment of autoimmune skin disease in 31 dogs..

Antihistamines in Horses

Practitioners may prefer to use antihistamines to reduce urticarial reactions and reduce pruritus in horses because these drugs usually have fewer side effects than steroids. The American Quarter Horse Association recommends a 10 day withdrawal prior to any competition.

Vet Prac News, Apr 2001. .

Prednisone Administered as a Transdermal Gel to Treat Allergic Dermatitis in a Cat

PZI and Low-Dose Insulin

The commercial production of traditional beef &/or pork insulins has declined as most human diabetic patients (the majority of the consumers) are being switched to human insulin products because of the reduced risk of allergic reactions. Protamine zinc insulin occurs as a sterile suspension of insulin modified by the addition of protamine sulfate and zinc chloride, and has a long duration of action (up to 30 hours). Therefore, treatment of many dogs and cats has been accomplished with once daily dosing of PZI.

U-20 and U-40 insulin allow for more accurate measurement of smaller doses required by many pets and birds. Use of U-100 insulin can result in morbidity or mortality caused by dosing errors.

Oral Anti-Diabetic Drugs

Methimazole for Feline Hyperthyroid Disease

Transdermal Methimazole Applied to Ear of Hyperthyroid Cats

Adrenal Disease in Male Ferrets

Adrenal gland disease is a common problem in middle-aged to older ferrets. The disease results in one or both of the adrenal glands producing abnormal amounts of androgens and/or estrogens, and can cause hair loss, itching, vulvar enlargement in females, prostate enlargement in male ferrets which can block the flow of urine, and in rare cases, bone marrow suppression. Although not usually a serious health concern, ferrets may have no relief from the itching that is associated with this disease if it is not treated.

Mitotane for Canine Hyperadrenocorticism

In veterinary medicine, mitotane is used primarily for the medical treatment of pituitary-dependent hyper-adrenocorticism (PDH) and palliative therapy of adrenal carcinoma, usually in dogs. Systemic drug availability has been found to be very poor from intact tablets in fasted dogs, and best when the powdered drug is mixed in oil and poured on dog food. The interaction between food and mitotane probably contributes to the variation in clinical response of dogs treated with the drug, because it appears that the efficacy is improved considerably when the drug is given with food. Because of the potentially severe toxicity associated with mitotane, clients should be instructed to wear gloves during and wash their hands after administering the medication, and to keep the medication out of reach of children or pets. Dogs with concurrent diabetes mellitus may have rapidly changing insulin requirements during the initial treatment period, and should be closely monitored until they are clinically stable. Clients should be advised of the symptoms of acute hypoadrenocorticism. Because of the potential severe toxicity associated with mitotane, clients should be instructed to wash their hands after administration and to keep the medication out of reach of children or pets.

Therapy for Chronic Canine Otitis

Treatment errors, over and under treatment, or inappropriate use of antimicrobial medication can result in a chronically diseased ear. The key to successful management of chronic canine otitis is early intervention, identifying a cause of the condition, and employing specific and appropriate therapy.

Ears with highly proliferative, chronic disease require deep cleaning and flushing before any topical therapy can be expected to help resolve the condition. Should a myringotomy be performed, the contents of the middle ear can be aspirated as soon as rupture occurs, and the middle ear can be flushed with normal saline or Tris-EDTA using a feline, open-tipped urinary catheter. “Just before the animal wakes, Tris-EDTA and a topical antimicrobial solution should be instilled and a parenteral prednisolone administered.”

“The pathogens isolated most frequently from chronic external and middle-ear infections include Staphylococcus intermedius, Malassezia pachydermatis, Pseudomonas species, Proteus species, Escherichia coli, and enterococcus. Selection of both systemic and topical antimicrobial medication is based on cytologic evaluation and culture and sensitivity results. Systemic antibiotics are mandatory… Treatment should continue until the infection is resolved (a minimum of 4 weeks). It is not uncommon for treatment of otitis media to continue uninterrupted for 8 to 12 weeks.”

Patricia D. White, DVM, MS of Atlanta Veterinary Skin & Allergy Clinic suggests that several compounded preparations may be appropriate.

Compendium on Continuing Education 21:8 August 1999, pg 716-28. .

Importance of Medication Vehicle

Topical antimicrobial therapy is an important part of the treatment regimen, and the vehicle is as important as the active ingredient. Most otic preparations are combination drugs (glucocorticoid plus antibiotic) in an oil or ointment base. Oils and ointments are occlusive, may hold or trap exudate, and may increase the risk of ototoxicity; such preparations are not desirable in cases of chronic otitis in which a moist exudate is present, the canal is stenotic, or the eardrum may be ruptured. The goal of treating a wet ear is to dry it. Solutions and suspensions are primarily composed of water; may contain an astringent (e.g., aluminum acetate); and are designed to evaporate over time, thus helping to dry the ear.” Topical antibiotics that are selected initially should be adjusted when the culture and sensitivity results are known.

“There is no single topical otic preparation that will satisfactorily treat all conditions. Practitioners tend to dispense a product based on clinical impressions or pick a favorite product rather than selecting one that has specific application for the current condition.” Direct application of medication to the ear canal will result in a higher concentration than that obtained with systemic medication.

Once you have identified the problem, we can compound an otic preparation to most appropriately treat each animal.

Compendium on Continuing Education 21:8 August 1999, pgs. 716-728. .

Antimicrobial/Anti-inflammatory Otic Suspensions, Anhydrous Preparations without Aminoglycosides

It is desirable to move away from commercially available aminoglycoside- antifungal-steroid otic preparations to avoid animoglycoside induced ototoxicity. Use of a formulation that substitutes a fluoroquinolone for an aminoglycoside constitutes a more effective and less toxic therapy, and is preferred if a tympanum rupture is expected. The efficacy and tolerability of a fluoroquinolone-clotrimazole-dexamethasone (FCD) otic suspension (10 drops per affected ear once daily) was compared with a standard topical treatment containing polymyxin B, miconazole and prednisolone (PMP) in a total of 140 dogs with clinical signs of acute or subacute otitis externa, Staphylococcus, Pseudomonas, Enterobacteriaceae and Malassezia were isolated from samples taken at inclusion. Each group received treatment for 7 or 14 days according to the clinical outcome on day 7. Treatments were equally effective, with a cure rate of 58.3% for the FCD prep and 41.2% for the PMP combination. Both medications were equally well tolerated by dogs, but FCD was superior in terms of pain relief, decrease in pus quantity and smell, response rate and investigator’s assessment on day 14.

Vet Dermatol. 2005 Oct;16(5):299-307.. A comparative study of two antimicrobial/anti-inflammatory formulations in the treatment of canine otitis externa..

While it is a common practice in some veterinary offices to add dexamethasone injection to clotrimazole solution to create an otic preparation with both antifungal and anti-inflammatory properties, it is more desirable to use an anhydrous preparation in the ear to reduce the risk of bacterial growth in the warm, moist environment. Anhydrous preparations also tend to have longer shelf lives. Avoid using products such as miconazole solution which has a high alcohol concentration to avoid irritating a sensitive ear.

Tris-EDTA Solution for Canine Otitis

Pain Management in Cats

Pharmacokinetic data developed in other species cannot be safely extrapolated to the cat. Feline deficiency of glucuronidation pathways results in slow metabolism of several NSAIDs, which prolongs the duration of effect and may lead to drug accumulation and toxicity.

Meloxicam for Analgesia in Dogs

A clinical trial was conducted to evaluate the safety and efficacy of meloxicam in dogs with chronic osteoarthritis. A scoring system assessed specific lameness, general stiffness, painful rise, exercise intolerance, and behavior, and demonstrated significant reductions in clinical signs of osteoarthritis following 4 weeks of drug therapy. Side effects were minimal in extent and duration. The findings of this investigation suggest that the efficacy, tolerance, and formulation of meloxicam oral suspension make it well suited for the treatment of chronic osteoarthritis in the dog.

Can Vet J 2000 Apr;41(4):296-300. .

Ketoprofen

Ketoprofen is a potent anti-inflammatory and analgesic which can be used for the management of surgical pain or chronic pain. The drug should not be given to animals with GI ulceration, impaired renal or hepatic function, or coagulation disorders. Ketoprofen should not be used preoperatively when noncompressible bleeding may be a problem. Occasional vomiting has been reported. When an NSAID or other drug that is potentially irritating to the GI tract is needed, topical preparations offer an excellent alternative. Pharmaceutical Research, Vol. 13, No. 1, 1996 reports (in humans) “a topical formulation of ketoprofen has been developed for the temporary relief of minor aches and pains of muscle and joints and to minimize gastrointestinal side effects after oral administration.”

Xylitol Poisoning in Dogs

Compounding pharmacists are now receiving requests from veterinarians to compound oral medications for dogs and cats in vehicles that are known to be free of xylitol. Xylitol is an artificial sweetener commonly used to sweeten human medications, gums, mouthwashes and candies, and while not toxic to humans, can be quite toxic to dogs. Xylitol is not absorbed from the gastrointestinal tract of humans, but is easily absorbed in dogs. Once in the bloodstream, xylitol acts like glucose, stimulating insulin secretion, which causes life-threatening hypoglycemia. Profound hypoglycemia can last for 1-2 hours following xylitol ingestion, and has frequently resulted in death. Many commercially available drugs labeled for humans, such as gabapentin oral suspension, contain xylitol as an inactive ingredient, and all human medications used in dogs should be scrutinized for xylitol content. Compounding pharmacists can play a valuable role for veterinarians and veterinary patients by providing xylitol-free suspensions of medications and by educating clients to avoid all xylitol-containing foods in their pets. It is not currently known if xylitol is toxic in cats, but for the present, xylitol must also be assumed to be toxic to cats.

Apomorphine to Stimulate Vomiting

Emetic drugs are usually administered in emergency situations after ingestion of a toxin. “Apomorphine is an opiate drug that acts as a potent central dopamine agonist to directly stimulate the CTZ. It can be administered PO, IV, or SC; the IM route is not as effective. It can also be applied directly to conjunctival and gingival membranes, using the tablet formulation, which can easily be removed once emesis is initiated. Vomiting usually occurs in 5-10 min. Although apomorphine directly stimulates the CTZ, it has a depressant effect on the emetic center. Therefore, if the first dose does not induce emesis, additional doses are not helpful. Because the vestibular apparatus may also be involved in apomorphine-induced vomiting, animals that are sedate and motionless will not vomit as readily as animals that are active. Because it can cause CNS stimulation, apomorphine is used cautiously in cats. Opiate-induced excitement in cats can be treated with naloxone (an opiate antagonist).” Apomorphine dosage for dogs: 4 mg/kg PO; 0.02 mg/kg IV; 0.3 mg/kg SC (from Merck Veterinary Manual, 8th edition, p. 1681); 0.25mg/kg (as a tablet) into the conjunctival sac (from Plumb’s Veterinary Drug Handbook, p.51)

Accidental Poisoning

Accidental poisoning is not a rare event; and veterinarians need to have access to antidotes. However, there are relatively few products specifically labeled for use in these instances, so it has not really been legal for veterinarians to have previously prepared antidotes for poisonings on hand in emergency rooms. For example, if a case of lead poisoning is diagnosed and the veterinarian needs some calcium EDTA as an antidote, there is no product available labeled for use in animals… Compounding offers opportunities for facilities to have [items such as calcium EDTA] on hand … for emergency treatment, in anticipation of a legitimate prescription.”

Intl J of Pharm Comp 1997 July/Aug; 1(4): 240. .

N-acetylcysteine as an Antidote for Acetaminophen Toxicosis

N-acetylcysteine (NAC) is the antidote of choice for the treatment of acetaminophen poisoning, one of the most common types of intoxication in dogs and cats. NAC acts principally by replenishment of intracellular glutathione stores and detoxification of the reactive metabolite (NAPQI). NAC acts as a scavenger of free radicals, blocks the conversion of hemoglobin to methemoglobin, and can reduce the extent of liver injury.

Dimercaptosuccinic Acid for Lead Poisoning in Cats

enicillamine for Long-Term Treatment of Lead Poisoning

Penicillamine chelates a variety of metals, including copper, lead, iron and mercury, forming stable water-soluble complexes that are excreted by the kidneys. Used primarily for its chelating ability in veterinary medicine, it is the drug of choice for copper storage-associated hepatopathies in dogs at a dose of 15mg/kg PO twice daily. Penicillamine may also be used in cystine urolithiasis (penicillamine combines chemically with cystine to form a stable soluble complex that can be readily excreted) and in a different dose for the long-term oral treatment of lead poisoning. “This drug should preferably be given on an empty stomach, at least 30 minutes before feeding. If the animal develops problems with vomiting or anorexia, three remedies have been suggested. 1) Give the same total daily dose, but divide into smaller individual doses and give more frequently. 2) Temporarily reduce the daily dose and gradually increase to recommended dosage. 3) Give with meals (will probably reduce amount of drug absorbed).”

Veterinary Drug Handbook, 2nd edition, Donald C. Plumb, Ed. . .

4-Methylpyrazole for Ethylene Glycol (Antifreeze) Poisoning

Therapy for ethylene glycol poisoning is aimed at preventing absorption, increasing excretion, and preventing metabolism of ethylene glycol to its toxic metabolites. Inhibition of liver alcohol dehydrogenase (ADH), the enzyme responsible for the initial reaction in the metabolic pathway, can be accomplished by giving a compound that combines with the enzyme and renders it inactive. The most effective ADH inhibitor in the dog is 4-methylpyrazole (4-MP), which unlike most competitive inhibitors (ethanol, propylene glycol, and 1,3-butanediol) does not contribute to CNS depression and increased serum osmolality. The recommended dose of 5% (50mg/ml) 4-methylpyrazole is 20 mg/kg body weight IV initially, followed by 15 mg/kg IV at 12 and 24 hr, and 5 mg/kg at 36 hr. While 4-MP is the recommended therapy in dogs, it is not appropriate for use in cats. Although it is non-toxic, it does not effectively inhibit EG metabolism unless administered to a cat at the same time as consumption of EG.

Am J Vet Res 1995;56:825.. .

Potassium Bromide for Seizures

Potassium bromide is frequently helpful in treating refractory seizures in animals. Because potassium bromide is excreted renally, it may also be preferable for use in animals that have developed hepatotoxicity while on other anticonvulsants. My compounding pharmacist prepares this as a liver flavored solution, which can easily be administered to dogs. I feel that it is important to inform my animal owners that potassium bromide solution is compounded from a reagent grade chemical, and is not a commercially available “drug.”

KBr is dosed on a weight basis. Maintenance doses range from 20-100 mg/kg body weight/day, and can be given as a single or divided dose. I usually dose at 30-40mg/kg/day as a single dose with food. Due to its long half-life, KBr can take up to four months to reach steady state; therefore, a loading dose may be required if therapeutic blood levels must be reached quickly. The loading dose is 400-600 mg/kg body weight and is administered orally over 30 to 60 minutes to avoid vomiting. A loading dose is not necessary if it is possible to keep the animal on other medications (as in a case of emerging hepatotoxicity) until levels of bromide are therapeutic (0.5-1.5 mg/ml), when the other anticonvulsant can be tapered off.

Mollyann Holland, D.V.M., Oklahoma City, OK. Diplomate, American College of Veterinary Internal Medicine.

Potassium Bromide Chewable “Treats” for Seizure Control

Chewable treats can be compounded to contain a variety of medications and flavored for the specific breed or pet. This dosage form has high patient acceptance and a low risk of owner misdosing.

Potassium bromide (KBr) can be also compounded as an oral solution which is easy to flavor and convenient for use as a loading dose. However, the risk of owner misdosing is greater than with a chewie or capsule.

Phenobarbital: Problems and Solutions

While phenobarbital is often used in veterinary medicine to treat seizure disorders, there are several concerns with its use:

• there are no commercially available veterinary approved products
• phenobarbital tablets for human use are small, hard, and unscored, making them difficult to divide for individualized dosing
• phenobarbital elixir has a high alcohol content, which is problematic for cats or any species when chronically administered
• phenobarbital induces CYP450 hepatic enzymes which can result in substantial drug interactions with oral anticoagulants, steroids, antibiotics, beta-blockers, theophylline, etc.
• phenobarbital is contraindicated in dogs with hepatic disease

When you wish to prescribe phenobarbital, please be aware that our compounding pharmacy can prepare an alcohol-free, appropriately flavored oral suspension, which is highly bio-available and very easy to use when administering a loading dose or when a flexible dose is needed. Once the maintenance dose is established, the dosage form can be switched to a capsule (with a lower risk of misdosing by the owner) or a flavored chewable medicated “treat”, with the added benefit of high patient acceptance.

Hormonal Therapy

Diethylstilbestrol (DES) has been used to treat estrogen responsive incontinence in spayed female dogs. The use of DES is contraindicated in cats as daily use has resulted in pancreatic, hepatic, and cardiac lesions.

Adrenergic Agonists

Phenylpropanolamine (PPA) is a weak alphaagonist that increases urethral sphincter tone and produces closure of the bladder neck, and is used to treat urethral sphincter hypotonus and resulting incontinence in dogs and cats.

Piroxicam for Canine Bladder Cancer

Traditional chemotherapy (using cisplatin, carboplatin, adriamycin, and others) has been used in canine Transitional Cell Carcinoma (TCC). The response has been rather disappointing with <20% of dogs having remission.

Interest in non-steroidal anti-inflammatory (NSAID) therapy began when dogs with various forms of spontaneous cancer had remission while receiving the NSAID piroxicam for pain control, and no other therapy. Two of the first dogs treated (one with metastatic carcinoma, one with undifferentiated sarcoma) had advanced cancer and had remission of their cancer when only receiving piroxicam. This has led to numerous studies of piroxicam in animals with cancer at Purdue University Veterinary Teaching Hospital (PUVTH). In an attempt to improve the response of TCC to therapy, PUVTH conducted a study comparing chemotherapy (cisplatin) alone to chemotherapy plus piroxicam. The combination of cisplatin and piroxicam was more effective against the cancer, but the combination treatment caused a rise in BUN. In several instances, the cisplatin therapy was withdrawn (so as to not cause renal damage) while the tumors were still shrinking.

Cancer Chemother Pharmacol. 2000;46(3):221-6.. Cisplatin versus cisplatin combined with piroxicam in a canine model of human invasive urinary bladder cancer..

Citrate Salts as Alkalinizing Agents

Citrate salts are a source of bicarbonate, but are much more palatable than bicarbonate preparations. “They are used as urinary alkalinizers when an alkaline urine is desirable and in the management of chronic metabolic acidosis accompanied with conditions such as renal tubular acidosis or chronic renal insufficiency. Potassium citrate alone has been used for the prevention of calcium oxalate uroliths. The citrate can complex with calcium thereby decreasing urinary concentrations of calcium oxalate… When urine is alkalinized by citrate solutions, excretion of certain drugs (e.g. quinidine, amphetamines, ephedrine, …tetracycline) is decreased, and excretion of weakly acidic drugs (e.g. salicylates) is increased. The solubility of ciprofloxacin and enrofloxacin is decreased in an alkaline environment [and patients] should be monitored for signs of crystalluria.” (Plumb’s Veterinary Drug Handbook, 2nd ed.) In combination with potassium citrate preparations, these agents may lead to severe increases in serum potassium levels: NSAIDs, ACE-inhibitors, cyclosporine, digitalis, heparin and others.

Fludrocortisone Acetate

Fludrocortisone is a long-acting corticosteroid with potent mineralocorticoid and moderate glucocorticoid activity. It is used in small animal medicine for the treatment of adrenocortical insufficiency, where it promotes sodium retention and urinary potassium secretion. It is commercially available only as the human product, a tablet containing 0.1 mg fludrocortisone acetate. The maintenance therapy for animals (particularly dogs) can require administration of multiple tablets for each daily dose. Therefore, it may be more convenient for owner and animal to administer fludrocortisone acetate as a flavored suspension, or single flavored solid dosage form.

Aluminum Hydroxide for Hyperphosphatemia

For dogs and cats, aluminum hydroxide is initially dosed at 30 – 90 mg/kg orally one to three times daily. A preparation that can be mixed with food may be preferred as it is more easily dispersed throughout ingesta. Dosage must be individualized, and serum phosphate levels should be evaluated at 10-14 days to determine optimum dosage.

Veterinary Drug Handbook, 3rd edition, Donald C. Plumb, editor. pp. 48-49. .

Would you like a topical medication that is difficult for an animal to lick off or that will adhere to a mucosal surface?

You can prescribe a medicated “polyox bandage” or “mucosal bandage”. When moistened, this medicated preparation will adhere to a wound or mucosal surface, thereby providing a protective barrier and increasing the contact between the medication and the affected area.

Wound and Incision Care – Prevent Licking

A common problem encountered by veterinarians and animal owners is preventing an animal from licking an incision or licking medication from the area to which it has been applied. In addition to injury to the wound, pharmacists and veterinarians must consider the consequences of internal consumption of an external preparation. To prevent an animal from licking, a medication can be compounded to contain an extremely bitter substance. Choices include diphenhydramine, quinine, or the non-therapeutic ingredient sucrose octaacetate. Sucrose octaacetate can be added at 1% to 5% to any topical dosage form and the bitterness usually prevents the animal from repeated licking of the area of application. Another way to protect a medicated area from licking is to incorporate the needed medication into CAP (Cellulose Acetate Hydrogen Phthlate) solution. Since CAP solution does not dissolve in an acidic pH, the animal’s saliva does not remove it from the skin. CAP solution can also be sprayed directly onto a wound or over stitches to protect them.

Phenytoin/Lidocaine Poly-Ox Bandage Used to Treat Leg Wound

Therapy for Severe Chemical Burns

Electrolyte Paste to Restore Fluid and Acid Base Balance in Horses

“Prolonged exercise in horses, particularly when performed in hot and humid conditions, brings about large fluid and electrolyte loses which, if not restored, may impair thermoregulatory responses and result in hyperthermia.” In horses, administration of oral rehydration solutions (ORS) is problematic, because many horses refuse to drink fluids containing electrolytes. Therefore, administration of ORS typically requires placement of a nasogastric tube with its inherent risks. An alternative is to give a concentrated electrolyte mixture as a paste. Leon et al. of Department of Veterinary Clinical Sciences, University of Sydney, NSW, Australia studied six Thoroughbred geldings to determine “whether oral administration of a concentrated electrolyte paste would promote the restoration of fluid, electrolyte, and acid base balance as well as fluid and electrolyte deficits induced by furosemide administration” (a standard model which induces significant contraction of plasma volume and consistent electrolyte deficit against which the effects of treatment could be measured).

As a general conclusion, horses that received concentrated electrolytes [and had free access] to water consumed more water, regained more weight, lost considerably less electrolytes in urine, and maintained plasma electrolyte concentrations and acid base balance closer to baseline values than did those that had ad libitum access to water only.” Administration of electrolyte paste provided a more practical source than supplementation using feed or salt blocks.

Am J Vet Res. 1998 Jul;59(7):898-903.. Effects of concentrated electrolytes administered via a paste on fluid, electrolyte, and acid base balance in horses..

Progesterone for Estrus Induction in Mares

According to Robert R. Foss, DVM, progesterone in sesame oil, 150 mg per day, IM is equally as efficacious as altrenogest. The optimal formulation is the combination of progesterone and estradiol 17-beta; the addition of estradiol provides a greater feedback than progesterone alone, so cessation produces a more dramatic response. The estradiol is somewhat protective against exacerbation of endometritis. Dr. Foss commonly uses this combination at 150 mg progesterone and 10 mg estradiol 17-beta, IM, daily for 10 days. Estrus will usually begin in 6-8 days with ovulation around day 10-12. This combination has been effective in situations where altrenogest has failed.

Prednisone (Oral) Ineffective in Horses

To be effective, oral prednisone must be absorbed and metabolized to its active form prednisolone.

We can compound prednisolone into the most appropriate dosage form, including oral pastes or “chewies” that horses will love!

Pentoxifylline

In horses, a dose of 8.5 mg/kg orally two times daily is recommended for reducing the cytokine effects in endotoxemia. For the treatment of navicular disease, 6 g/day orally for 6 weeks should be used.

Compendium 23(7), July 2001, 603-4. .

Anti-Diarrheals for Foals & Horses

Treatment of diarrhea should always be based on establishing a diagnosis and correcting the basic cause. Anti-diarrheal products are not a substitute for adequate fluid and electrolyte therapy when dehydration or shock threatens. When the veterinarian deems anti-diarrheal therapy is appropriate, the following options may be considered.

According to James L. Becht, D.V.M., M.S., Diplomat ACVIM, preparations containing bismuth subsalicylate seem superior to those containing kaolin, pectin, or activated charcoal for treating the foal with diarrhea. Bismuth subsalicylate neutralizes bacterial toxins, has some antibacterial activity, and may exert an antisecretory effect. It can be administered at a dosage of 4 oz q 6h; darkened feces will result. If no effect is seen within 48 hours, continued administration is probably not indicated. (105th Ohio VMA).

Wendy E. Vaala, V.M.D., Diplomate ACVIM reports (ACVIM 16th Veterinary Medical Forum) that delayed gastric emptying and gastroduodenal dysmotility can be improved in some foals with metoclopramide (0.25-0.6 mg/kg, PO q4-6h), erythromycin (1.0-2.0 mg/kg PO q6h), or cisapride (10 mg/kg PO q6h). If colic, ileus, and gastric reflux are present, Dr. Vaala recommends an abdominal sonogram to rule out the presence of an intussusception prior to initiating prokinetic therapy. Diarrhea may be treated symptomatically with bismuth subsalicylate (1-2 ml/kg, PO, q4-6h) and may also respond to psyllium administration. Intestinal probiotics containing Lactobacillus bacteria … may be given to foals receiving antibiotics to help reestablish intestinal flora.

Adult horses may be treated with bismuth subsalicylate 1 oz per 8 kg of body weight PO TID-QID (Clark and Becht 1987).

Headshaking in Horses

Headshaking in horses may include additional signs such as nose rubbing, striking at the nose with the forelegs, or active avoidance of light, warmth, or wind on the face. Newton et al studied 20 mature horses with typical headshaking of 2 week to 7 year duration, and concluded that the etiopathology may be a trigeminal neuritis or neuralgia. In 12 of 20 horses, drug therapy was initiated. Cyproheptadine (CP) alone was ineffective but the addition of carbamazepine (CM) resulted in 80-100% improvement in 80% of cases within 3 to 4 days of beginning drug therapy. Seven cases were treated with a combination of CM (4 mg/kg, three to four times daily) and CP (0.2-0.5 mg/kg every 12 to 24 hours).

Carbamazepine alone has been effective in 88% of cases. Some headshaking horses have responded well to CM doses of 1.6 – 2.4 grams every six hours without apparent side effects. Horses are treated for 10 to 20 days and if they respond, the treatment is discontinued. If clinical signs of headshaking recur, treatment is restarted. In practice, there is a realistic possibility of controlling but not curing headshaking with carbamazepine therapy at the present time. Other studies have reported that cyproheptadine alone was beneficial in more than two thirds of treated horses.

Equine Vet J. 2000 May;32(3):208-16.. Headshaking in horses: possible aetiopathogenesis suggested by the results of diagnostic tests and several treatment regimes used in 20 cases..

Equine Vet J Suppl. 1998 Nov;(27):28-9.. Characterisation of headshaking syndrome--31 cases..

J Am Vet Med Assoc. 2001 Aug 1;219(3):334-7.. Owner survey of headshaking in horses..

Antifungal Therapy for Avian Species

In avian species, the most frequent causes of infection have shifted from gram-negative bacteria to gram-positive bacteria and Candida (often non-albican) species. There is a decreased susceptibility of many non-albicans species to available antifungal drugs, perhaps as a consequence of nondiscriminate azole use.

The efficacy of terbinafine has been improved when administered in combination with azoles for treatment of azole resistant oral candidiasis and aspergillosis. Because terbinafine was administered successfully in an African gray parrot at 15 mg/kg every 12 hours for 30 days without adverse effects, it may have potential for use in systemic aspergillosis in these azole-sensitive species. Caution should be used in avian patients with liver or renal disease.

Veterinary Clin North Am Exot Anim Pract. 2003 May;6(2):337-50, vi. .

Treatment of a Systemic Fungal Infection in a Parrot with Itraconazole Flavored Suspension and Nebulized Clotrimazole

Enrofloxacin in Birds

Enrofloxacin is highly active against most gram-negative bacteria. Doses of 15 mg/kg orally twice daily have maintained effective drug concentrations in most of the psittacine species that have been tested. Senegal parrots have required TID dosing for moderately resistant organisms. Keven Flammer, DVM, Dip ABVP, reports successful treatment of E coli, Klebsiella, and Proteus infections. He states that oral administration is well tolerated, but that IM administration should be avoided, and never used for repeated dosing, due to irritation at the site of injection. The IM formulation can be given orally but is unpalatable, even when mixed with flavoring. Dr. Flammer notes that an oral suspension can be compounded and appropriately flavored.

Haloperidol for Feather-Plucking and Self-Mutilation

Neuropeptides, particularly dopamine, are implicated in many self-mutilating disorders. The 1993 Proceedings of the Association of Avian Veterinarians (pg. 119-120) reports the dopamine antagonist haloperidol is currently being used on cockatiels, lovebirds, ring-neck parakeets, African Greys, and several species of cockatoos and Amazon parrots. The indications for use in these birds have included severe feather plucking, mutilation of skin and muscle over the back, chest and legs, wing web mutilation, and Amazon foot necrosis syndrome. Side effects from the use of haloperidol have included depression, depressed appetite, excitability and anorexia. (In most birds, side effects disappeared after discontinuing the drug for several days and then retrying at a lower dose.) One study reported normal behavior was maintained “by administering haloperidol at approximately 0.4 mg/kg body weight/day for approximately seven months.”

Journal of Small Animal Practice 1993; 34:564-566. .

Haloperidol for Feather Plucking

Efficacy of oral supplementation with L-lysine in cats latently infected with feline herpesvirus

Maggs et al. of the College of Veterinary Medicine, University of Missouri examined the effects of orally administered L-lysine on clinical signs of feline herpesvirus type 1 (FHV-1) infection and ocular shedding of FHV-1 in latently infected cats. Fewer cats and eyes were affected by conjunctivitis, and onset of clinical signs of infection was delayed on average by 7 days in cats receiving L-lysine 400 mg once daily for 30 days, compared with cats in the control group. Significantly fewer viral shedding episodes were identified in the treatment group cats, compared with the control group cats. This dose caused a significant but short-term increase in plasma L-lysine concentration without altering plasma arginine concentration or inducing adverse clinical effects.

Am J Vet Res. 2003 Jan;64(1):37-42.. Efficacy of oral supplementation with L-lysine in cats latently infected with feline herpesvirus..

Dextromethorphan

Of the seven major human cough suppressants, only dextromethorphanis indicated for treating cough in small animals. If after reviewing the indications and contraindications, cough suppression is desired, the available human products must be screened carefully as a very limited number contain dextromethorphan without other potentially harmful ingredients. Typically, the dose in dogs and cats is 1 to 2 mg/kg three to four times daily. Human products are not flavored to an animal’s taste, and may require administering a significant volume (typical strength is 15 mg/5 ml) to adequately dose an average size dog.

Stool Softeners

Docusate (DSS) can be used to assist in the passage of hard or dry feces that may occur secondary to dehydration or use of opioid analgesics or metoclopramide. While capsules hide the bitter taste, they can not be divided for appropriate dosing in smaller animals. The recommended dose in dogs and cats is 2 mg/kg once daily. For more severe cases, appropriately dosed DSS enemas may offer an alternative to phosphate-solution enemas.

Ursodiol for Gallstones

The purpose of this study, reported in Am J Health-Syst Pharm (Vol. 52) was to prepare an oral dosage form of the bile acid ursodiol (also known as ursodeoxycholic acid) from commercially available capsules and to determine the short-term stability of this formulation. The formula used for this extemporaneous compound was found to be stable for up to 35 days.

Ursodiol in a Dog with Chronic Hepatitis

A dog with severe cholestasis secondary to chronic hepatitis was treated with ursodeoxycholic acid (ursodiol) orally. After 2 weeks of daily treatment, the dog was more active and had an improved appetite. Monthly serum biochemical determinations and analysis of individual bile acid profiles documented improvement in hepatobiliary tests and a marked reduction in the concentrations of potentially hepatotoxic endogenous bile acids. These effects were maintained for approximately 6 months.

J Vet Intern Med. 1997 May-Jun;11(3):195-7.. Use of ursodeoxycholic acids in a dog with chronic hepatitis: effects on serum hepatic tests and endogenous bile acid composition..

Studies have found an extemporaneously compounded ursodiol suspension to be stable for up to 35 days refrigerated. This drug is well absorbed orally and enters the liver directly from the portal system, and is then secreted into bile. Ursodiol should be administered orally as the first-pass effect is vital for effectiveness.

Aminocaproic Acid for Degenerative Myelopathy (DM) in Dogs

The chances of successful treatment are improved if the therapy is begun early in the course of DM rather than later. A response to the drugs should be evident within the first 7-10 days.

Chlorpromazine for Anti-Emesis

Chlorpromazine (Thorazine®) is a phenothiazine and works at the emetic center, the chemoreceptor trigger zone, and peripheral receptors; it is this veterinarian’s “all purpose anti-emetic of choice” for cats.1 Chlorpromazine may cause extrapyramidal symptoms in cats when administered at high doses. The drug may discolor urine pink or red-brown, cause mild sedation, and may potentiate hypotension in dehydrated patients. Phenothiazines should not be given within one month of worming with an organophosphate agent. The recommended oral doses in dogs and cats is 3.3 mg/kg PO one to four times daily. Due to extensive first pass metabolism2, it may be necessary to reduce the dose in animals with liver disease. A liquid concentrate can be appropriately flavored for dogs or cats.

Managing Anorexia in Uremic Dogs and Cats

H2-receptor antagonists (cimetidine, ranitidine, and famotidine) can be useful to reduce gastric acid secretion. Increased gastrin concentrations in serum during chronic renal failure may stimulate excessive secretion of gastric acid and cause ulcer formation. Some uremic dogs and cats dramatically increase their interest in food and food intake after therapy with an H2 blocker. According to a presentation at the Atlantic Coast Veterinary Conference by Dennis J. Chew, DVM, Dip and C.A. Buffington, DVM, some uremic animals may need this medication for an extended period of time (months to rest of their lives). Much of the experience of these veterinarians has been either with cimetidine at an initial dose of 10 mg/kg, followed by 5 mg/kg PO BID or famotidine at 1 mg/kg daily.

Doxycycline for Prophylaxis and Treatment of Osteoarthritis in Dogs

Prophylactic administration of doxycycline (a tetracycline) has markedly reduced the severity of canine osteoarthritis (OA) in weight-bearing regions of the medial femoral condyle, and therapeutic administration of oral doxycycline has been shown to reduce the severity of articular cartilage breakdown in various animal models of OA. This disease modifying effect is associated with reductions in the levels of active and total collagenase and gelatinase in articular cartilage of the involved joint.

A prospective, clinical study of eighty-one dogs with OA secondary to spontaneous cranial cruciate ligament (CCL) rupture concluded that doxycycline inhibits nitric oxide production in cartilage in dogs with CCL rupture, and that doxycycline may have a role in the treatment of canine OA. Dogs with OA secondary to CCL rupture were divided into 2 groups before surgery. The Doxy-CCL group (n = 35) received 3 to 4 mg/kg doxycycline orally every 24 hours for 7 to 10 days. The CCL group (n = 46) received no treatment. Synovial fluid, articular cartilage, synovial membrane, and CCL samples were collected during surgery or immediately after euthanasia from healthy dogs (control group). Total nitric oxide concentrations measured in cartilage were significantly lower in the Doxy-CCL group than in the CCL group, but were not different from those measured in the control group.

In another study, ten healthy adult mongrel dogs underwent transection of the left anterior cruciate ligament, which resulted in a marked decrease in bone mass, with increased osteoclastic activity and increased bone formation. Doxycycline treatment did not significantly affect either bone formation or bone resorption. The authors concluded that doxycycline protects against joint breakdown in this OA model via inhibition of matrix metalloproteinases in articular cartilage, rather than through an effect on subchondral bone.

Vet Surg. 2001 Mar-Apr;30(2):132-9.. The effects of doxycycline on nitric oxide and stromelysin production in dogs with cranial cruciate ligament rupture..

J Rheumatol. 1996 Jan;23(1):137-42.. Effects of oral doxycycline administration on histomorphometry and dynamics of subchondral bone in a canine model of osteoarthritis..

J Rheumatol Suppl. 1995 Feb;43:149-51.. Modification by oral doxycycline administration of articular cartilage breakdown in osteoarthritis..

J Am Vet Med Assoc. 1997 Sep 15;211(6):719-22.. Effect of stanozolol on body composition, nitrogen balance, and food consumption in castrated dogs with chronic renal failure..

Cisapride: a Prokinetic Drug

Cisapride (Propulsid® – Janssen Pharmaceutica), was removed from the U.S. and Canadian markets by its manufacturer because of serious cardiac effects in humans. However, cisapride is now available as a bulk chemical for veterinary use only and can be compounded as per your prescription order.

Cisapride is chemically related to metoclopramide, but unlike metoclopramide, it does not cross the blood-brain barrier or have antidopaminergic effects or cause extrapyramidal reactions. Cisapride “is more potent and has broader prokinetic activity than metoclopramide, increasing the motility of the colon, esophagus (in cats and guinea pigs), stomach, and small intestine… [Cisapride] has been used in managing gastric stasis, idiopathic constipation, gastroesophageal reflux, and postoperative ileus in dogs and cats. Practitioners found cisapride especially useful in managing chronic constipation in cats with megacolon; in many cases, it alleviated or delayed the need for subtotal colectomy. Cisapride was also used in managing cats with hairball problems.”

Hairball Remedy

Cat and ferret owners continually search for specialized foods and treats that their pets will readily consume and will also be effective for hairball prevention or elimination. Call us for a customized, flavored hairball remedy for your patients!

Stanozolol

Anabolic steroids such as stanozolol have been used to treat geriatric dogs. These drugs can increase nitrogen and mineral retention so that the body can better utilize dietary protein. As a result, the dog’s appetite may improve, resulting in more strength, energy, and weight gain. There is one reported case of the use of stanozolol (0.5 mg/kg, SQ, BID, PRN) to stimulate appetite in a rabbit. However, this class of drugs is not without potentially serious side-effects which must be considered before using them. Anabolic steroids should be used with caution in animals with heart, liver, or kidney problems, or in animals with breast or prostate cancer. Stanozolol should not be used in pregnant animals, during lactation, in young animals, or in male breeding animals. Anabolic steroids may increase the effects of warfarin and other anticoagulants.

In dogs, reported side effects are mainly androgenic, including increased aggression, increased activity, weight gain and mood alterations. However, in cats with and without chronic renal failure, there are reported cases of hepatotoxicity that appear to be related to the use of stanozolol.

J Am Vet Med Assoc. 1997 Sep 15;211(6):719-22.. Effect of stanozolol on body composition, nitrogen balance, and food consumption in castrated dogs with chronic renal failure..

Can J Vet Res. 2000 Oct;64(4):246-8.. The effect of stanozolol on 15nitrogen retention in the dog..

J Am Vet Med Assoc. 1997 Sep 15;211(6):719-22.. Effect of stanozolol on body composition, nitrogen balance, and food consumption in castrated dogs with chronic renal failure..