Pharmacotherapeutics in small mammals (Proceedings)
Pharmacokinetic studies in exotic small mammals are lacking and, therefore, most of the dosages used in these species are based on empirical data, observations, and experience. Because drug uptake depends on factors such as age, sex, physiology, disease state, diet, etc., it is important for us as veterinarians to know some of the pharmacobiologic, physiologic, and anatomic characteristics of these species. It should also be noted that most of the drugs used in exotic small mammals are extralabel, so very few drugs are approved by the U.S. Food and Drug Administration (FDA) for use in these animals. The U.S. Animal Medicinal Drug Use Clarification Act enables veterinarians to use drugs approved for human and other animal use on animals other than those for which they are approved, if the reasoning is sound. This act requires that owners sign an informed consent form for extralabel drug use. Because most drugs are not approved by the FDA for use in these animals, it may be warranted for the owners to sign a consent form when registering their pet.1
This review will outline drug administration sites, compounding, and some of the issues involved in selecting an antibiotic, analgesic, or nonsteroidal, anti-inflammatory drugs for use in exotic small mammals.
CompoundingExotic animal practitioners face daily challenges to meet the pharmaceutical needs of their small mammal patients. Because there are few approved medications for use in these patients, attempts to meet these challenges include: extralabel use of human and domestic animal products; compounding by the practitioner; use of compounding service; using medicated feeds; and using imported pharmaceutical productions.2 There may be both legal and ethical issues that the practitioner must be aware in using any of the aforementioned strategies.
In the U.S., compounding of animal drugs is only permitted if it is conducted in accordance with established laws. These laws require that compounding be done by or on an order of a licensed veterinarian, within the context of a valid veterinarian/client/patient relationship, and from approved human or veterinary drugs. Compounded products must be prescription only.
Although compounding is a useful tool for exotic practitioners, it can sometimes lead to incompatibilities between active and nonactive ingredients. A well trained pharmacist can help avoid pitfalls of incompatibilities.
In small mammal medicine, the most common indication for compounding is the preparation of medications for per os administration. In cases when animals refuse to take a medication because of the taste, compounding using various flavor additives may be useful. For example, flavors which rabbits generally accept include: lettuce, carrot, parsley, celery, banana crème, vanilla butternut, and pineapple.