Compounding is the customized manipulation of a drug by a veterinarian, or by a pharmacist upon the prescription of a veterinarian, to meet the needs of a particular patient. Veterinarians need to be aware that all forms of compounding may impact the potency, stability, pharmacokinetics, and ultimately, the safety and efficacy of a drug. The decision to use a compounded preparation should be driven by the veterinarian (not pharmacist) and must occur within a veterinarian-client- patient relationship compliant with the federal VCPR and additional federal and state regulations including the Animal Medicinal Drug Use Clarification Act (AMDUCA). The veterinarian should make that decision using evidence-based medicine. The compounder should convey whether a product has been compounded from an approved drug or bulk drug substance.
Use of a compounded preparation should be limited to:
- Patients where their specific needs cannot be met with an FDA-approved animal or human drug product;
- Patients for which no other method or route of drug delivery is practical;
- Drugs for which there is a reasonable expectation of safety, efficacy, and stability in the specific compounded form in the target species;
- Disease conditions for which a quantifiable response to therapy or drug concentration can be monitored;
- If compounded medications are used in food-producing animals then adequate scientific information must exist to establish appropriate withdrawal/ withholding times.
Compounding from FDA-approved products
Preparations compounded from FDA-approved animal or human drug products are consistent with current extralabel drug use regulations, provided certain conditions are met. However, veterinarians should verify that compounding is in compliance with applicable state laws and regulations as they may vary by jurisdiction on the specifics of legally compounded preparations.
Compounding from bulk drug substances
Preparations compounded from bulk drug substances for use in animals are unapproved new animal drugs under the Federal Food, Drug and Cosmetic Act. Use of preparations compounded from bulk drug substances carries potential legal risk. Bulk drug substances are the raw active pharmaceutical ingredients utilized in the manufacturing of drug products. However, FDA recognizes the medical necessity of compounding from bulk drug substances in limited circumstances and exercises enforcement discretion in these situations.
The bulk drug substances utilized in the preparation of compounded products may or may not be of the same quality as those utilized in FDA-approved products. Pharmacy-compounded products may have minimal safety, efficacy data, or stability data, and the standards for potency, purity, and other manufacturing quality parameters are not the same as FDA-approved products.
The AVMA recognizes that there are circumstances in which the use of medications compounded from bulk drug substances is medically necessary. AVMA advocates on behalf of the veterinary profession for the following uses of these unapproved substances:
- In all animals (including non-food-producing free-ranging wildlife) when:
- There is no FDA-approved drug product (veterinary or human) from which to compound the needed preparation or
- The FDA-approved drug product is not commercially available or
- The needed compounded preparation cannot be made from the commercially available FDA-approved drug product.
- In addition, in food-producing animals only the following are appropriate for compounding from bulk drug substances:
- Certain compounded poison antidotes or
- Certain compounded agents used for euthanasia or depopulation
- Certain compounded sedatives and anesthetics for free-ranging wildlife species
Extralabel drug use (ELDU) algorithm