Canine Cushing's Case Files: The ins and outs of detection and treatment-Case file: 5 Questions Veterinarians Ask (Sponsored by Dechra Veterinary Products)

Case file: 5 questions veterinarians ask the Dechra Veterinary Products Technical Services Team

Diagnosing canine hyperadrenocorticism can be fairly straightforward, based on history and clinical signs, along with the results of diagnostic tests that are readily available to practitioners. Once a diagnosis of pituitary- or adrenal-dependent hyperadrenocorticism is made, VETORYL® (trilostane) Capsules are the only FDA-approved drug indicated for medical treatment of either condition. VETORYL Capsules are backed by a company with a veterinary technical services team ready to answer your questions.

In this case file, the Dechra Veterinary Products Technical Services Team answers five questions they are frequently asked about canine hyperadrenocorticism and VETORYL Capsules. When you identify canine Cushing's cases and you have questions about this treatment, contact the team who wants to help you successfully manage your patients.

Q: What sizes of VETORYL Capsules are available, and is an exact dose required when starting treatment for canine hyperadrenocorticism?

A: VETORYL Capsules are available in 10, 30, 60, and 120 mg sizes. The starting dose for the treatment of hyperadrenocorticism in dogs is 1.0 to 3.0 mg/lb (2.2 to 6.7 mg/kg) once a day, based on body weight and capsule size. VETORYL Capsules should always be administered with food to ensure maximum serum levels and, thus, efficacy. Dechra Veterinary Products recommends using the lowest effective dose consistent with individual response; round the dose down if the calculated amount is between available capsule sizes and assess the patient's response to that dose in 10 to 14 days.

Q: What is the recommended monitoring protocol, and what information should be obtained from the owner at each recheck appointment?

A: Ten to 14 days after starting VETORYL Capsules, re-examine the dog and perform an adrenocorticotropic hormone (ACTH) stimulation test four to six hours after VETORYL Capsules have been administered with food. Re-examine the dog at 30 days and 90 days after beginning VETORYL Capsules, and every three months thereafter. At a minimum, this monitoring should include a thorough history and physical examination, ACTH stimulation test (conducted four to six hours after VETORYL Capsules administration, with food), and serum biochemical tests (with particular attention paid to electrolytes and renal and hepatic function). Before each ACTH stimulation test is performed, be sure to confirm that the owner gave the VETORYL Capsules that morning, and that the drug was given with a small amount of food.

We cannot overemphasize the importance of talking with the owner at each recheck appointment about how the dog is doing at home. Specifically, ask:

• Are the clinical signs of hyperadrenocorticism well controlled in your dog?

• Does your dog exhibit any new signs or conditions of concern to you?

This information is critical when interpreting the results of the ACTH stimulation and other biochemical tests. Dechra Veterinary Products encourages veterinarians to contact the Veterinary Technical Services Team if assistance is needed in interpreting test results.

Q: Should dogs that have test results consistent with a diagnosis of hyperadrenocorticism but no compatible clinical signs be treated?

A: The decision to treat canine hyperadrenocorticism must first be based on history and physical examination findings suggestive of the disease. The results of a serum biochemistry panel, CBC, urinalysis, and urine protein:creatinine ratio can support but not confirm a diagnosis of hyperadrenocorticism.

Endocrine function tests (such as the low-dose dexamethasone suppression test and/or ACTH stimulation tests) should be performed when a patient exhibits clinical signs consistent with hyperadrenocorticism. None of the tests used to evaluate cortisol concentrations have 100% sensitivity or specificity; to avoid false-positive test results, the veterinarian should have a high degree of suspicion that the patient in question may have hyperadrenocorticism and has no other condition that could cause a stress-related increase in cortisol concentration. Dechra Veterinary Products does not recommend treating hyperadrenocorticism in patients with suggestive diagnostic test results but no compatible clinical signs. Likewise, patients with clinical signs suggestive of hyperadrenocorticism (bilateral alopecia, weight gain, pot-bellied appearance, etc.) should not be treated if endocrine function tests do not confirm the disease.

Q: Are compounded trilostane preparations the same product as VETORYL® (trilostane) Capsules?

A: Compounded trilostane preparations are not the same as the FDA-approved product, VETORYL Capsules. It is recognized that reformulation of VETORYL Capsules is necessary when specific patients require trilostane in dosage strengths and/or forms that are not commercially available. FDA regulations do not permit compounding of animal products from bulk active ingredients. If you need a different strength or form of trilostane for a patient, ask that the pharmacist only compound to your specifications using the FDA-approved contents in VETORYL Capsules as the active ingredient for your prescription. This ensures your patient will at least receive a medication containing an active ingredient that has undergone FDA scrutiny for consistency, quality and efficacy.

In addition to the concern about the active ingredients in compounded medications, other variables can affect a patient's response and outcome when using compounded medications. A recent study evaluating 96 batches of compounded trilostane products purchased from eight compounding pharmacies found that the average percentage label claim for each batch ranged from 39% to 152.6%.1 Thus, patients could be severely underdosed or overdosed when receiving these compounded preparations. Additionally, 20% of the batches analyzed did not meet the dissolution criteria; thus, patients receiving these compounded preparations may not be able to absorb the drug from their gut because the formulation is not properly dissolving after ingestion. In conclusion, the study's authors stated, "Compounded trilostane products should be used with caution as they may jeopardize the management of dogs with [hyperadrenocorticism] and potentially impact patient safety."1

VETORYL® (trilostane) Capsules

Q: What resources are available from Dechra Veterinary Products to help veterinarians and their teams successfully manage canine hyperadrenocorticism?

A: Many! Client brochures, monitoring forms, algorithms, and team training and continuing education modules are available to clinics free of charge (www.dechrace.com). Many of the resources can be downloaded from the Dechra website (www.dechra-us.com) or can be obtained through your local Dechra Veterinary Products sales manager.

Furthermore, Dechra Veterinary Products has a staff of in-house registered veterinary technicians, veterinarians, and field-based veterinarians who are available for case consultations and for reporting suspected adverse events.

REFERENCE

1. Cook AK, Nieuwoudt CD, Longhofer SL. Pharmaceutical evaluation of compounded trilostane products. J Am Anim Hosp Assoc 2012; 48:228-233.

The Dechra Veterinary Technical Services Team can be reached at this toll-free phone number: 866-933-2472.

Dechra Veterinary Products Technical Services Team:

Dana Fertig, DVM, MS — Director of Technical Services

Andy Fox, DVM — Technical Services Veterinarian

Cathy Just, DVM — East Coast Field Veterinarian

Nancy Zimmerman, DVM, DABVP — West Coast Field Veterinarian

Dosha Atwell, RVT — Technical Services

Teresa Olson, CVT — Technical Services

Hyperadrenocorticism affects many adult dogs. Whether the disease is pituitary-dependent (80% to 85% of spontaneous cases) or adrenal-dependent (15% to 20% of cases), the clinical and laboratory abnormalities associated with it result from chronic hypercortisolemia. Clinical signs of hyperadrenocorticism at the time of diagnosis can vary widely, and they develop so gradually that owners often mistake the signs for "normal" aging. Being aware of the more subtle signs of canine hyperadrenocorticism can be key to early diagnosis and initiation of therapy.

COMMON CLINICAL SIGNS OF CANINE HYPERADRENOCORTICISM

Whenever possible, pituitary-dependent hyperadrenocorticism and adrenal tumors should be differentiated to help guide therapy and patient monitoring. Early diagnosis and management of canine hyperadrenocorticism may not only improve the patient's clinical signs but may also keep the more severe consequences of Cushing's syndrome from developing.

Learn more with these online resources

Go to the Dechra Veterinary Products CE Learning Center at www.dechrace.com and choose one of the online CE modules to learn the latest on managing feline hyperthyroidism and canine hyperadrenocorticism. Plus earn free CE!

• Diagnosing and treating canine hyperadrenocorticism

Presented by Audrey K. Cook, BVM&S, MRCVS, DACVIM, DECVIM, and David s. Bruyette, DVM, DACVIM

• Cushing's disease: Inside and out

Rhonda Schulman DVM, DACVIM, and John Angus, DVM, DACVD

• Diagnosing and treating feline hyperthyroidism

Presented by Andrew J. Rosenfeld, DVM, DABVP

Then get your whole team on the same page, by visiting the Team Meeting in A Box section at www.dechrace.com

• Stop getting burned by ear infections

How you handle otitis externa and ear infections can make or break client bonds—and dogs' well-being. Use this Team meeting in a Box to create a team approach to help pet owners and heal patients.

• Coping with Cushing's syndrome

Pets with Cushing's syndrome suffer from a chronic illness that will be managed throughout the pet's life, not cured. This Team Meeting in A Box will help you deliver a successful team-wide approach.

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