Without clear statutory authority, FDA has proposed to expand its legal authority over veterinarians and veterinary compounding pharmacies in its newly released “Revised Draft Guidance on Compounding Animal Drugs from Bulk Drug Substances,” (#256) as announced on November 19, 2019.

FDA continues to describe the use of certain compounded medications for animals as violations of the Federal Food, Drug, and Cosmetic Act (FD&C Act), which it will not enforce under certain prescribed circumstances.

As stated in Guidance #256

The policies described in this document aim to protect human and animal health by limiting the use of animal drugs compounded from bulk drug substances primarily to situations in which a veterinarian is acting within a valid veterinarian client-patient relationship (VCPR) 3 and there is no medically appropriate drug that is FDA approved, conditionally approved, or on the Index of Legally Marketed Unapproved New Animal Drugs for Minor Species (indexed) to treat the animal.

While FDA states that the “FD&C Act does not generally distinguish between compounding animal drugs from bulk drug substances and other methods of animal drug manufacturing . . . [t]he law permits compounding of animal drugs [only] when the source of the active ingredient is a finished FDA-approved drug, and not a bulk drug substance.”  (Emphasis added).

FDA proposed certain labeling and adverse reporting requirements for drugs compounded pursuant to patient-specific prescriptions for nonfood-producing animals, drugs compounded for office stock for nonfood producing animals, and drugs compounded for use as antidotes for food-producing animals.  Veterinarians administering or dispensing antidotes used for food-producing animals must also provide scientifically-based withdrawal times.

Also, without statutory authority, FDA requests input from the purportedly regulated community about a “List of Bulk Drug Substances for Compounding Office Stock Drugs for Use in Nonfood-Producing Animals or Antidotes for Food-Producing Animals.

The proposed list includes:


Apomorphine hydrochloride – Indication: For the induction of emesis in dogs. Dosage form: 6.25 mg subconjunctival tablets, 3.125-6.25 mg/ml subconjunctival solution, and 2.5 mg/ml injectable solution.

Cisapride – Indication: For management of gastrointestinal disorders in cats, including: general constipation and constipation from megacolon. Dosage form: 2.5 and 5 mg oral tablets or capsules, and 5-10 mg/ml oral suspension.

Dipyrone – Indication: For the treatment of severe, acute fever in Shar-Pei dogs and Shar-Pei mixed breed dogs suffering from Shar-Pei fever. Dosage form: 250 and 500 mg/ml injectable solution.

Guaifenesin – Indication: For muscle relaxation in the horse during anesthetic induction and/or surgery. Dosage form: 50 g soluble powder to be reconstituted into a solution for IV infusion with the addition of 500 ml (10%) or 1000 ml (5%) sterile diluent.

Metronidazole benzoate – Indication: For the treatment of feline inflammatory bowel disease in cats. Dosage form: 80 mg/ml suspension.

Miconazole nitrate – Indication: For treatment of fungal keratitis in horses. Dosage form: 1% or 2% miconazole nitrate ophthalmic solution or ophthalmic ointment.

Potassium bromide – Indication: For initiation of treatment for seizures in dogs. Dosage form: 250 mg/ml oral solution.

Tacrolimus – Indication: For treatment of dogs with keratoconjunctivitis sicca (KCS) that is non-responsive to cyclosporine. Dosage form: 0.01– 0.03% tacrolimus ophthalmic drops.


Awaiting nominations


Awaiting nominations

Interested parties should submit nominations for additional bulk drug substances as described in the #256 Appendix.