Phenylbutazone/Cimetidine Powder
Phenylbutazone/Cimetidine is a compounded formulation containing Phenylbutazone, Cimetidine, prepared by Mixlab for veterinary use. Available by prescription.
Powder medications are meant to be mixed into food or treats, not given on their own (since most pets won’t lick up plain powder). The key is to mix it into something tasty so your pet eats the entire dose.
How to Give It:
- Measure the dose using the included scoop or follow the instructions. If you’re unsure how much to give, ask your vet or pharmacist.
- Mix it with a small amount of soft food or treat—like wet food, baby food (meat flavor), peanut butter (xylitol-free), yogurt, or cheese. Use just enough to hide the powder so your pet finishes it all in one go.
- Stir it well to blend the powder in evenly. Add a splash of water if needed to make it smoother.
- Offer it when your pet is a little hungry, and watch to make sure they eat the whole thing.
- If your pet refuses, try something else they love next time. For cats, you can also try smearing the paste on their paw to lick off (only if safe and comfortable).
- For large animals, mix the powder into a small portion of feed with water or molasses, then follow with the rest of their food once they’ve eaten the medicated part.
- Store the powder in a cool, dry place with the lid closed tightly.
Never give powder straight into your pet’s mouth—it can be dangerous if inhaled.
This compounded formulation combines phenylbutazone, a non-steroidal anti-inflammatory drug (NSAID), with cimetidine, an H2-receptor antagonist — two different drug classes. In compounding practice, clinicians may consider a combination like this for a multi-targeted approach. Your veterinarian determines whether it is appropriate based on your animal's diagnostic findings.
At a pharmacological level, the two active ingredients function through distinct mechanisms. Phenylbutazone acts by inhibiting the cyclooxygenase (COX) enzymes, which are responsible for the synthesis of prostaglandins that mediate inflammatory responses. By reducing the production of these mediators, it addresses systemic and localized inflammation within the tissues. Cimetidine acts as a competitive inhibitor of histamine at the H2-receptors located on the gastric parietal cells. This action suppresses the secretion of gastric acid, providing a gastroprotective element to the protocol. This dual-action approach acts to address inflammatory concerns while managing the gastric environment. Your veterinarian will determine if this specific combination is appropriate based on your horse's weight, health status and individual clinical needs.
This description reflects the general pharmacology of the active ingredient's drug class; your veterinarian determines whether this approach is appropriate for your animal.
Prescription only. Use only under the direction of a licensed veterinarian. This information is not a substitute for veterinary diagnosis, prescribing or monitoring. Compounded drugs are not approved by the FDA for safety or effectiveness.
Commonly observed effects of phenylbutazone/cimetidine may include gastrointestinal changes such as loose stools, decreased appetite or transient behavioral shifts. Because phenylbutazone can influence renal blood flow and the mucosal lining of the gastrointestinal tract, your veterinarian will monitor for signs of gastric ulceration or changes in kidney function during the course of administration. Ensuring your horse remains well-hydrated and has access to appropriate forage is a critical component of the management approach.
This medication is typically used with extra caution or avoided in patients with known kidney or liver disease, pre-existing gastrointestinal ulcers or cardiac compromise. It is also carefully evaluated in pregnant or lactating mares, as the safety profile for developing foals has not been extensively characterized. Because cimetidine can inhibit certain liver enzymes, it may influence the metabolism of other oral medications, so a complete history of all current prescriptions and supplements is essential. Contact your veterinarian promptly if you observe any unexpected changes in water intake, swelling of the lower limbs or signs of abdominal discomfort. Always consult your veterinarian about the appropriate duration of use and whether your horse's competitive status requires a withdrawal period. Phenylbutazone (an NSAID) is subject to detection in equine medication-testing programs and specific withdrawal times vary by jurisdiction and governing body.
Yes. Phenylbutazone/cimetidine is a prescription medication and can only be dispensed by a licensed pharmacy like Mixlab upon receipt of a valid authorization from a licensed veterinarian. Mixlab verifies all prescriptions before any medication is prepared or sent to your home or stable.
Yes. While individual components may be available in various commercial forms, Mixlab can compound this specific combination into formats such as flavored oral pastes or powders to facilitate easier administration for your horse. Your veterinarian will determine the most appropriate compounded strength and format based on your animal's individual requirements.
Veterinarians discuss the addition of cimetidine because phenylbutazone, like many NSAIDs, can influence the protective lining of the stomach. Cimetidine is considered for its ability to support acid secretion, which may be part of a management approach for the gastric environment while the phenylbutazone addresses inflammatory conditions.
Owners should monitor for changes in appetite, water consumption or the consistency of the horse's manure. You should also look for signs of physical discomfort or swelling and contact your veterinarian immediately if you observe any behavior that deviates from the horse's normal routine.
