Prednisone versus Prednisolone: Which drug for which species?

While prednisone and prednisolone have historically been considered therapeutically equivalent when used in veterinary medicine, recent studies have proven that they are not. It is now well-accepted in veterinary medicine that while prednisone and prednisolone may be therapeutically equivalent in dogs and humans, they are not in cats and horses. Researchers Graham-Mize and Rosser administered 10 mg total dose of either prednisone or prednisolone to cats in order to determine comparative pharmacokinetics of each drug. The AUC (ng/ml/hr) and Cmax (ng/ml) of oral prednisolone was 5 fold and 11 fold higher following administration of prednisolone compared to an equivalent oral dose of prednisone: 3230 and 1400, respectively, following oral prednisolone compared to 672.63 and 122, respectively following oral prednisone. Although the study was not designed to discriminate differences in oral absorption versus hepatic conversion, the authors nonetheless demonstrate the superiority of oral prednisolone to prednisone in cats. Until further studies are conducted, most veterinary clinicians agree that prednisolone (not prednisone) should be utilized in feline patients.In 2002, researchers had demonstrated a superiority of prednisolone over prednisone in treating horses with recurrent airway obstruction (heaves). In this crossover study, 5 horses were given the following treatments: prednisone tablets, prednisone liquid, prednisolone tablets, prednisolone liquid and i.v. prednisolone sodium succinate (positive control). Blood samples were taken before drug administration and at selected time points during a 24 hour period. Serum concentrations of prednisone and prednisolone were determined in order to evaluate gastrointestinal absorption and hepatic metabolism. Serum concentrations of the endogenous glucocorticoid hydrocortisone were also determined as an indicator of the biological activity of the drugs. Both prednisolone tablets and liquid were absorbed rapidly, with prednisolone detectable in serum within 15 min of administration and with peak concentrations occurring within 45 min. Small amounts of prednisone were detected in the serum samples after administration of both prednisone tablets and liquid. The active metabolite prednisolone was not detected in serum samples after administration of prednisone liquid and was detected in serum samples from only one horse after administration of prednisone tablets. Endogenous hydrocortisone production was suppressed when horses received prednisolone. The results of these studies indicate that prednisone has poor efficacy for the treatment of heaves because it is poorly absorbed and the active metabolite prednisolone is rarely produced. In contrast, prednisolone tablets have excellent bioavailability and should be useful as a therapeutic agent in horses.Consult our compounding pharmacist about customized dosage forms and strengths. Caution: Transdermal application of prednisolone (or other corticosteroids) to the ear is not recommended due to a high likelihood of epidermal atrophy of the ear pinnae with chronic use. The ear tips will flop with time and may not return to normal shape even after withdrawal of the prednisolone.

Veterinary Dermatology 15 (s1) 2004, pp 10.

Bioavailability and activity of prednisone and prednisolone in the feline patient.

Click here to access the PubMed abstract of this article.

Equine Vet. J. 2002 May;34(3):283-7

Prednisone per os is likely to have limited efficacy in horses.

Click here to access the PubMed abstract of this article.

Safety and Efficacy of Ocular vs Parenteral Apomorphine for Induced Emesis in Dogs

A study published in October 2008 retrospectively evaluated the efficacy of a compounded 2mg ocular insert of apomorphine versus a compounded 1mg/ml apomorphine injection. Either parenteral or ocular apomorphine dosage forms were sent to veterinary clinics with a case study report form requesting case-specific information. Information collected included breed, body weight, time from placement of the insert until emesis, and any information available regarding the nature of the toxin and clinical signs. Clinicians were asked to grade the severity of adverse effects on a subjective scale of 0 to 5, with 5 being most severe and 0 being absent. The adverse effects listed included prolonged vomiting, tachycardia, excitation, respiratory depression, bradycardia, sedation, and ocular irritation. Hypotension was not specifically included because of the difficulty of monitoring this while treating the dog. The clinician was also asked to grade the ease of product use for each case. Case reports for more than 5000 dogs were ultimately reviewed.For the ocular insert group, approximately 67% of dogs developed emesis between 3 and 10 minutes following placement of the insert. Approximately 83% of the dogs had emesis within the 15-minute time interval. Median time to emesis was 6 minutes, 7.2% of dogs experienced emesis after 15 minutes, and 9.3% did not have emesis at all. When the drug was administered IV, emesis occurred rapidly with a success rate of 90.6% and a median time to emesis of 1 minute. Difference in success rate between the IV and ocular insert groups was not significant (p=0.399).The prevalence of adverse effects with the IV route was less than the ocular route; however, the prevalence of tachycardia and sedation were higher with the IV group. Tachycardia was detected in 0.6% of dogs treated with the ocular insert and 15.6% of those treated IV. In the ocular insert group, sedation occurred with a frequency of 11.1%, whereas the IV group had a frequency of 43.8%. For the ocular insert group, ocular irritation in 82% of dogs was also reported, but of these, 80% had severity scores of 1, which meant detected but not clinically relevant. If reports with a score of 1 were disregarded, the frequency of irritation decreased to 16.2%. In 6.3% of dogs, the clinician experienced some difficulty with use of the insert, either in placing the insert or in maintaining the insert in the conjunctival sac; and some dogs actively resisted placement of the insert while other dogs were successful in dislodging the insert once it had been placed, leading to discontinuous administration. The ease of use scores seemed to become better with time, suggesting that with experience, the clinicians became more skilled in using the inserts.Researchers also observed that dogs weighing more than 25kg seemed less responsive to a 2mg ocular dose of apomorphine. Researchers concluded that an insert with a larger quantity of apomorphine should be utilized for larger dogs and that safeguards should be employed to prevent administration of larger dose inserts to smaller dogs.Apomorphine has not been commercially available to veterinarians for several years. For this reason, compounding pharmacists have been supplying apomorphine to veterinarians in various dosage forms to have immediately available for emergency use. Dosage forms include compressed tablets, powders for reconstitution into ocular or injectable solutions, and injectable solutions for parenteral administration. In light of the results of this study, it would appear that compounded ocular solutions might be superior to either injections or solid ocular tablets or inserts. Kits can be prepared containing apomorphine that can be reconstituted for use as an isotonic ophthalmic solution and subsequently can be administered as an injection if emesis is not successfully induced after ophthalmic administration. Veterinarians interested in obtaining these dosage forms or kits may contact our compounding pharmacy.

Am J Vet Res. 2008 Oct;69(10):1360-5.

Safety and efficacy of an ocular insert for apomorphine-induced emesis in dogs.

Click here to access the PubMed abstract of this article.

Pyridostigmine Oral Liquid for Treatment of Myasthenia Gravis

Myasthenia gravis (MG) is a common cause of generalized weakness in dogs and cats. With optimal care, the prognosis for remission and a normal life are good. “Unfortunately, drugs used to diagnose and treat myasthenia gravis are frequently unavailable” but during manufacturer shortages, compounding pharmacists can provide needed medications.The drug used most commonly to treat MG is pyridostigmine bromide at a dose of 1-3 mg/kg orally two to three times daily. “It is extremely important to note, however, that pyridostigmine bromide should not be compounded with methylcellulose-containing vehicles, as methylcellulose has been shown to completely inhibit the oral absorption of pyridostigmine from the gastrointestinal tract.2 For animals not responding to pyridostigmine, corticosteroids (e.g., prednisone for dogs, prednisolone for cats) can be administered at 0.5 mg/kg orally every other day. Immunosuppressive doses of corticosteroids are not recommended as they may worsen muscle weakness.”

International Journal of Pharmaceutical Compounding. Sep/Oct 2008; 12(5):398-401

Veterinary Compounding for Myasthenia Gravis

Click here to access the abstract of this article.2 Neurology 1981; 31(2):145-149.

Compounding for Feline Lymphoma

Feline lymphoma is one of the most common cancers in cats and presents with a variety of lesions and symptoms. Feline lymphoma, like human lymphoma, is classified into low, medium and high-grade categories depending on the anatomic location and degree of malignant cell growth in affected organs. There are many clinical reports published describing the diagnosis, treatment and prognosis of cats with lymphoma; however, there has been little correlation between treatment, histologic grade and clinical outcome. Until 1999 there had only been one published study that followed treatment and outcomes for a group of cats with intestinal lymphoma. Of 40 cats evaluated, 29 cats with low-grade lymphoma in this study had a significantly greater response (69%) to medical therapy (chlorambucil and prednisone) and underwent complete remission with a medical survival time of greater than 20.5 months.The 11 cats in the high-grade group (treated with a variety of multiple drug combinations) showed a much poorer response to therapy.A retrospective study reviewed 667 cases of feline lymphoma and identified cats suffering from low-grade lymphoma. This study concluded that 92% of cats treated with chlorambucil and prednisone responded to treatment for more than 2.5 years and showed a disease-specific median survival time of 967 days.Both of these studies indicate that the combination of oral chlorambucil and prednisone are excellent treatment modalities for cats suffering from low-grade lymphoma.The dosage range for prednisone or prednisolone for treatment of feline lymphoma is 5-10mg daily. In spite of the success demonstrated by treatment with prednisone in the previously mentioned studies, recent pharmacokinetic work indicates that prednisolone has a much better oral bioavailability (i.e., higher levels of drug in the body) as compared to prednisone in cats. Veterinarians may find that providing prednisolone instead of prednisone with chlorambucil may further increase remission rates and survival times in cats with lymphoma. Both prednisolone and chlorambucil are extremely bitter drugs and many cats object strongly to the taste. By collaborating with veterinarians and pet owners, our compounding pharmacist can play an active role in providing palatable, individualized oral chemotherapeutic regimens of prednisolone and chlorambucil for cats with lymphoma.

Eur J Comp Gastroenterol 1999;4:5–11.

Feline gastrointestinal lymphoma: 67 cases (1988–1996).

Click here for more information.

J Am Vet Med Assoc. 2008 Feb 1;232(3):405-10.

Outcome of cats with low-grade lymphocytic lymphoma: 41 cases (1995–2005)

Click here to read the PubMed abstract of this article.

VetDermatology. 2004; 15 (Suppl. 1):9.

Bioavailability and activity of prednisone and prednisolone in the feline patient.

Click here for more information.

Managing Tracheal Collapse in Toy and Miniature-breed Dogs

Collapsing trachea is a commonly recognized problem with toy and miniature-breed dogs (e.g., Toy Poodles, Yorkshire Terriers, Pomeranians, Maltese, Chihuahuas) that is associated with weakness of the tracheal cartilage resulting in collapse of the airway.Tracheal collapse can sometimes be helped with surgery, but medical management remains the treatment of choice. Treatment strategies involve cough suppression, and the drug therapy of choice has historically been the combination of hydrocodone and homatropine used orally three to four times daily.As long as shortages of commercially available hydrocodone/homatropine products continue, our pharmacy can play a valuable role in providing compounded hydrocodone/homatropine oral suspensions, capsules and chewable treats in canine-friendly flavors for dogs with tracheal collapse.

Vet Clin North Am Small Anim Pract. 2000 Nov;30(6):1253-66, vi.

Tracheal collapse. Diagnosis and medical and surgical treatment.

Click here to read the PubMed abstract of this article.

Cetirizine Pharmacokinetics in Cats

While chronic dosing studies and safety and efficacy studies in allergic cats still need to be conducted, that the pharmacokinetic profile of cetirizine suggests that it is a promising alternative to glucocorticoid therapy in allergic cats. Presently, commercially available forms of cetirizine are not easily adjusted to cats. Cetrizine tablets for adult humans are 10mg tablets and could be halved to achieve an appropriate dose for a 5kg cat.Cetrizine products labeled for human children are available in 5mg chewable grape-flavored tablets or a 1mg/ml grape-flavored syrup. Because of the flavoring and the volume of liquid that would have to be administered, cetirizine products labeled for human children would be very difficult to administer to cats.Commercially-available cetirizine dosage forms are not particularly cat-friendly, and because cetirizine shows much promise for therapy of allergies in cats, veterinarians may wish to contact our compounding pharmacy to assist in preparing dosage forms of cetrizine that can be easily administered to cats.

Am J Vet Res. 2008 May;69(5):670-4.

Pharmacokinetics of cetirizine in healthy cats.

Click here to read the PubMed abstract of this article.

Aspirin Therapy for Cats

A retrospective study in cats receiving high dose aspirin (> or = 40 mg/cat q72h) and cats receiving low-dose aspirin (5 mg/cat q72h) showed equally efficacious anti-platelet effect in either group but a significantly lower incidence of adverse effects in the low dose aspirin group.Capsules containing 5mg of aspirin can be compounded in lactose, flavored with various powdered flavors. Pet owners can administer the capsules intact, or if the act of pilling is too stressful for the cat, the contents of the capsule can be sprinkled in a small amount of moist food for the cat to consume at will.Clinical effects and plasma concentrations of fentanyl after transmucosal administration in three species of great ape.“fentanyl can be administered transmucosally to captive orangutans and gorillas for sedation. With further study on formulation, it may also become useful in chimpanzee protocols. The transmucosal route may also be clinically useful for acute pain management.”

J Zoo Wildl Med. 2004 Jun;35(2):162-6

Clinical effects and plasma concentrations of fentanyl after transmucosal administration in three species of great ape.

Click here to access the PubMed abstract of this article.

Emergency Emetic Kits for Canine Drug Units

Canine members of police departments are frequently trained to detect drugs and other illicit substances. Although training techniques are now being modified to avoid ingestions, most dogs were historically trained to aggressively paw, mouth, or bite any object that was suspect. This behavior greatly increases the risk of oral ingestion of these very potent, very dangerous drugs. Veterinarians are now offering training and emergency emetics to police officers so that they may provide life-saving decontamination measures. Compounding pharmacists can work with local police and veterinarians to provide emesis kits to ensure that these valuable public servants are afforded the best chance for survival when faced with an accidental ingestion.

JAVMA, 2006 Apr 1;228(7):1028-32

Toxicologic hazards for police dogs involved in drug detection.

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.

Click here to access the PubMed abstract of this article.

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 metoclopramide or other medications. 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.

Merck Veterinary Manual, 8th Edition, pp. 1691

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.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.

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.

Click here to access the PubMed abstract of this article.

Aminocaproic Acid for Degenerative Myelopathy (DM) in Dogs

DM appears with relative frequency only in the German Shepherd breed (GSD); confirmation of the diagnosis is important in other breeds before assuming that they have DM of GSD. During the past two decades, R.M. Clemmons, DVM, Ph.D., and other researchers at the University of Florida have provided important new insights into the pathoetiology of DM. Recently, they have found that when combined with the history, neurologic signs, CSF protein concentration and EMG, an elevated CSF acetylcholinesterase level helps confirm the diagnosis. It is increasingly clear that DM is caused by an autoimmune disease attacking the nervous systems of patients, leading to progressive neural tissue damage. In many respects, DM is similar to Multiple Sclerosis in human beings.The Integrative Medical Approach to Treatment of Degenerative Myelopathy involves four basic approaches: 1) exercise, 2) dietary supplementation, 3) medication, 4) other supportive measures. Conventional medicine has little to offer patients with DM. On the other hand, use of exercise, certain vitamins and selected drugs have delayed or prevented progression of DM in many afflicted dogs.Clemmons et al have found 2 medications which appear to prevent progression or result in clinical remission of DM in up to 80% of patients – aminocaproic acid (EACA) and n-acetylcysteine (NAC). They propose that circulating immune-complexes lead to endothelial cell damage in the vessels of the CNS. Subsequently, fibrin is deposited in the perivascular spaces. When this degrades (point of action of aminocaproic acid), inflammatory cells are stimulated to migrate into the lesions. The inflammatory cells release prostaglandins and cytokines (point of action of vitamin E and C) which lead to the activation of tissue enzymes and the formation of oxygen free-radicals (point of action of acetylcysteine) which, in turn, leads to tissue damage.They recommend giving EACA as a flavored solution, 500 mg orally every 8 hours. A “source for EACA is to have a compounding pharmacy make the solution from chemical grade EACA.” The only side effects that have been attributed to EACA have been occasional gastrointestinal irritation. This has presented a problem only in a few patients, typically those with pre-existing GI problems. The only known drug interaction is with high dose estrogen compounds.N-Acetylcysteine is a potent anti-oxidant which has powerful neuroprotective effects. Clemmons et al give 75 mg/kg divided in 3 doses a day for 2 weeks; then, 3 doses every other day. The N-acetylcysteine must be diluted to a 5% solution; otherwise, it will cause stomach upset. “This new treatment is expensive unless purchased through compounding pharmacies.” NAC can produce vomiting (due to the sodium content of the pharmaceutical product, which requires high concentration of base to buffer) and may increase the bleeding time. Giving fresh ginger 30 minutes before NAC or administering NAC with food (or on a full stomach) often reduces this effect.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.

1. Todd R. Tams, DVM, Dip ACVIM in CA VMA C/E Conf Procd, 2000
2. Veterinary Drug Handbook 3rd edition, Donald C. Plumb, ed.; pp. 129-30

Managing Anorexia in Uremic Dogs and Cats

h4-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 h4 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.

The Capsule Report, Vol. 19, No. 10, Jan. 2001

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.

Click here to access the PubMed abstract of this article.

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.

Click here to access the PubMed abstract of this article.

J Rheumatol Suppl 1995 Feb;43:149-51

Modification by oral doxycycline administration of articular cartilage breakdown in osteoarthritis.

Click here to access the PubMed abstract of this article.

Vet Clin North Am Small Anim Pract 1997 Jul;27(4):863-81

Slow-acting, disease-modifying osteoarthritis agents.

Click here to access the PubMed abstract of this article.

Arthritis Rheum 1992 Oct;35(10):1150-9

Effect of stanozolol on body composition, nitrogen balance, and food consumption in castrated dogs with chronic renal failure.

Click here to access the PubMed abstract of this article.

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 pure 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.””Cisapride appeared to be well tolerated by dogs and cats. Adverse reactions to cisapride have not been reported to the United States Pharmacopeia’s Veterinary Practitioners’ Reporting Program… Disorders of GI motility are common and frustrating clinical problems in dogs and cats. Cisapride, with its extensive prokinetic action, was a welcome addition to veterinary medicine.””Life after cisapride: Prokinetic drugs for small animals.” Patricia M. Dowling, DVM, MS, DACVIM, DACVCP Veterinary Medicine, September 2000, pp. 678-685

Doses:

Dogs –

As a promotility agent: initially 0.5mg/kg three times daily to reduce regurgitation associated with megaesophagus: 0.55mg/kg orally one to three times daily, no less than 30 minutes before feeding. As an antiemetic: 0.1-0.5mg/kg orally every 8 hours.

Cats –

For chronic constipation: initially, 2.5mg (for cats up to 10#) or 5mg (cats 11-15#), or up to 7.5mg (for cats over 16#) three times daily, 30 minutes before food, in combination with stool softener and bulk agent.

Cisapride is contraindicated in patients in whom increased GI motility could be harmful (e.g., perforation, obstruction, GI hemorrhage). Absorption of other orally-administered drugs may be affected. Cisapride may enhance anticoagulants’ effects; additional monitoring and anticoagulant dosage adjustments may be required. Cisapride may enhance the sedative effects of benzodiazepines. Clients should be advised to monitor the animal and report any adverse effects.

Veterinary Drug Handbook, 3rd edition, Donald C. Plumb, editor. pp. 139-140

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!

Managing Tracheal Collapse Patients

Collapsing trachea is a commonly recognized disease of toy and miniature-breed dogs. Treatment strategies involve cough suppression, and the drug therapy of choice has historically been hydrocodone.As long as shortages of commercially available hydrocodone/homatropine products continue, our pharmacy can play a valuable role in providing compounded hydrocodone/homatropine oral suspensions, capsules and chewable treats for tracheal collapse patients. While the ingredient homatropine may not play a significant role as a cough suppressant for dogs, inclusion of homatropine greatly discourages human abuse of hydrocodone by virtue of its anticholinergic side effects.We can compound as a canine-friendly flavor (e.g. liver).

Vet Clin North Am Small Anim Pract. 2000 Nov;30(6):1253-66, vi.

Tracheal collapse. Diagnosis and medical and surgical treatment.

Click here to access the PubMed abstract of this article.

Compounding for Feline Lymphoma

Feline lymphoma is one of the most common cancers in cats and presents with a variety of lesions and symptoms resulting from various cell types, degrees of dissemination and rate of progression.Recent studies have shown cats treated with chlorambucil and prednisone responded to treatment for more than 2.5 years. Recent pharmacokinetic work indicates that prednisolone has a much better oral bioavailability as compared to prednisone in cats. Both prednisolone and chlorambucil are extremely bitter drugs and many cats object strongly to the taste. By collaborating with veterinarians and pet owners, our compounding pharmacist can play an active role in providing palatable, individualized oral chemotherapeutic regimens of prednisolone and chlorambucil for cats with lymphoma.

Eur J Comp Gastroenterol 1999;4:5–11.

JAVMA, February 1, 2008; 232(3):405-410.

Outcome of cats with low-grade lymphocytic lymphoma: 41 cases (1995–2005)

Click here to access the PubMed abstract of this article.

Veterinary Dermatology 15 (s1) 2004, page 10

Mirtazapine for Appetite Stimulation in Dogs and Cats

Mirtazapine (Remeron™-Organon) is approved as an antidepressant for use in humans and has activity both as an alpha2 receptor antagonist and as a potent 5HT3 antagonist.A side effect noted in humans taking this drug is appetite stimulation. Pharmacy faculty at the Mississippi State College of Veterinary Medicine used mirtazapine in a dog after all other attempts at appetite stimulation had failed, and were very pleased to find that mirtazapine restored appetite almost immediately in this dog.In another case, a physician used mirtazapine to treat anorexia and nausea in his Boston Terrier with chronic renal failure. Due to the vast improvement in the animal’s quality of life for one month preceding its death, the dog’s primary care veterinary clinic conducted a series of uncontrolled field trials using mirtazapine over the next 4 years in 24 dogs and 17 cats with GI symptoms that were marginally responsive or refractory to standard remedies. “Mirtazapine therapy led to a robust response in 12 animals, improvement compared with standard treatment in 16 cases, and an equivocal response in 13 animals. The most vigorous responses were observed in patients in chronic renal failure or receiving concurrent chemotherapy for neoplastic disease.”Many veterinarians have started using mirtazapine to stimulate appetite in both dogs and cats.There have been no controlled studies and dosing is still empirical, but most dogs are dosed at 0.6mg/kg orally every 24 hours and cats are dosed at 3.75mg/cat orally every 48-72 hours. The terminal half-life of mirtazapine in humans is more than 40 hours, and mirtazapine is eliminated partially through conjugation with glucuronide. For this reason, dosing intervals of less than 48 hours are not recommended for cats, as accumulation is likely. Mirtazapine is not commercially available in an oral suspension; however, compounding pharmacists have formulated suspensions upon the request of veterinarians and have anecdotally reported success with this dosage form. For cats that are vomiting as well as anorectic and cannot swallow or retain oral medications, veterinarians have instructed compounding pharmacists to formulate transdermal gels of mirtazapine (3.75mg/0.1ml), which also have left veterinarians with a positive impression of clinical efficacy. Obviously, further studies are needed to determine stability, safety and efficacy of these compounded dosage forms, but until such evidence is available, veterinarians may wish to try these dosage forms in cases that are refractory to traditional methods of appetite stimulation.

Veterinary Forum, February 2006, pages 34-36