Prescription Drugs for Horses

The FDA regulates drugs for your horses' protection
by Dave Sauter, DVM

The Food and Drug Administration (FDA) is the governing body that regulates the development, production and sale of medications in the United States, both human and animal. Here, we’ll review the basic rules and regulations governing the pharmaceutical industry.

FDA Approval
All new drugs must be approved by the FDA before they go to market. Pharmaceuticals have to demonstrate through mandated, standardized methods--including blinded control studies--that the new drug is safe and effective for the intended animal and medical purpose. The company must establish that the drug can be manufactured consistently, batch after batch; that it remains stable; and determine a reliable shelf life. Monitoring continues once the drug is in production, and the FDA also regulates marketing and advertising activities associated with the drug.

Generic Drugs
Generic drugs must be approved by the FDA just like name-brand drugs. After the patent has expired on the “pioneer” drug, other companies are then permitted to produce it. They must demonstrate that the generic is the bioequivalent to the brand-name version in dosage form, efficacy, safety, strength, route of administration, quality and intended use. Like the pioneer drug, they must follow the same Good Manufacturing Practices (GMP) mandated by the FDA in federally inspected plants. Once generics are allowed, consumer prices for the product go down substantially.

Extra-label Use
The costs associated with bringing drugs to market are enormous. Consequently, it is not surprising that there are many situations where approved veterinary medications are simply unavailable. The necessary research and development, not to mention the formidable FDA approval process and subsequent monitoring requirements, are economically unattractive to manufacturers. Fortunately, practitioners are permitted to use their discretion and utilize medications beyond the label indications. For example, Adequan is labeled for arthritis in the knee but is commonly employed for arthritis of other joints. Naxcel is an antibiotic labeled for respiratory infections but is commonly used for other infections. Prior to Gastroguard, there were no gastric ulcer medications approved for horses. Human ulcer products were routinely prescribed “extra-label.”

Dispensing vs. Prescribing
Generally, all new pioneer drugs are prescription. In order to provide prescription drugs, a valid veterinarian-client-patient relationship must be established. This means that the veterinarian has examined and is familiar with the patient and has determined that the drug is appropriate. This also provides an opportunity to review proper dosing, storage and administration.

Most veterinary prescription products are dispensed directly by the attending veterinarian. It is permitted and sometimes necessary to prescribe medications through outside sources, such as extra-label use of a human medication not kept in the clinic inventory but available at a local human pharmacy.

The FDA has the authority to change a prescription drug status to over-the-counter (OTC). This is done for products that have been on the market long enough and no longer require veterinarian supervision. An example of this is procaine penicillin, which is readily available from most feed stores. These OTC products are still regulated and monitored, and the manufacturing facilities are inspected by the FDA.

Direct marketing of health products to horse owners through magazines, catalogs, and other publications is becoming commonplace. Also, online pharmacies are becoming more prevalent. These alternative sources are a permitted, legal avenue for prescriptions, just so long as they are licensed pharmacies with a registered pharmacist. If they are not licensed, they are selling products illegally. The products sold illegally might be FDA approved drugs. Worse is if the illegal pharmacies are selling illegal, unapproved products, which could be unsafe, impure and poor quality. If there is no mention of FDA approval on the site, beware. It is easy to check the licensing status of an online pharmacy by calling the State Health Department. When in doubt about a product, check with your veterinarian.

Background on the FDA
The Food and Drug Administration is an agency of the United States Department of Health and Human Services. Its origin dates back to June of 1906, when President Theodore Roosevelt signed into law the Food and Drug Act. This was in response to concern over adulteration and misbranding of food and drugs on the American market. FDA powers were expanded in 1938 by the Food, Drug and Cosmetics Act, granting greater authority over drugs, drug labeling, safety standards, inspections, enforcement and standards for food and cosmetics. This legislation was in response to numerous injurious products that made it to the marketplace, such as radioactive beverages, cosmetics that caused blindness, and the 1937 Elixir Sulfanilamide tragedy, during which over 100 people died because the elixir used an untested toxic solvent.

Today, the FDA regulates companies and industries that account for roughly $1.5 trillion worth of consumer goods and medicines. The agency is responsible for the safety and effectiveness of prescription drugs, biologics (e.g., vaccines and blood products), over-the-counter medicines, medical devices, cosmetics, nutritional supplements and all food products except meat and poultry. The Center for Veterinary Medicine is the branch of the FDA that regulates food, food additives and drugs given to animals. Animal vaccines are regulated by the USDA, not the FDA.