OTC and Rx. What's the difference?

In veterinary medicine, as in human medicine, medications can be over-the-counter (OTC) or prescription.

OTC medications, which are obtained without a prescription, are drugs that can be used to treat conditions that don't necessarily require a vets care and have been proven to have high safety standards when used in the treatment of these conditions. Examples of OTC products include (but are not limited to):

• Frontline Plus or K9 Advantix
• Glucosamine and Chondroitin supplements
• Vitamins
• Most shampoos

OTC products may be federally regulated by FDA if there is a labled claim to the cure, prevention, mitigation or treatment of a disease (such as diphenhydramine for allergies), EPA (if product is an insecticide as used in flea and tick products) or not federally regulated if there is no medical claim (nutritional supplements).

Prescription medications, which require a prescription prior to dispensing by a pharmacist, are sometimes called legend drugs because they carry a warning (legend) that says "Rx only" or "Caution: Federal (U.S.A.) law restricts this drug to use by or on the order of a licensed veterinarian". What's the difference? "Rx Only" medications are drugs FDA approved for use in humans. However, it is a common practice for vets to use these medicines in animals as well. An example would be Tapazole (methimazole) used in both humans and cats for hyperthyroid disease.

Drugs that have the warning "Caution: Federal (U.S.A.) law restricts this drug to use by or on the order of a licensed veterinarian", are drugs FDA approved for use in animals and can only be used in animals and can only be prescribed by a veterinarian. An example would be Deramaxx (deracoxib).