Phenylbutazone Paste

Paste medications are thick and sticky, usually given by mouth using a syringe or tube. They’re often used for dewormers or other oral meds in horses, dogs, and cats. The key is to aim for the back of the mouth so your pet swallows the paste instead of spitting it out.

For Horses:

1. Set the dose on the syringe if it has markings (usually based on weight).
2. Stand beside your horse, not in front, and have someone hold them if possible.
3. Gently insert your thumb into the side of the horse’s mouth (between the teeth) to open it.
4. Insert the syringe into that gap and squirt the paste toward the back of the tongue.
5. Lift the horse’s head slightly and encourage swallowing by stroking the throat or gently blowing on the nostrils.
6. Watch for licking or chewing—that means they swallowed. If paste spills out, check how much was lost and contact your vet if unsure.
7. You can offer a little water afterward and reward them with a treat like a carrot if allowed.

For Dogs & Cats:

1. Gently open your pet’s mouth or slip the syringe into the side of it.
2. Aim toward the back of the tongue and squirt the paste in.
3. Hold the mouth closed briefly, and rub the throat or blow gently on the nose to encourage swallowing.
4. Give praise or a treat afterward to make it a positive experience.

Aftercare:

1. Wipe your pet’s mouth if needed.
2. Clean or recap the syringe as instructed.
3. Store the tube according to label directions.

Tip: Paste can feel weird to pets at first. For horses, try giving applesauce by syringe ahead of time so they get used to the sensation.

Veterinarians most commonly consider phenylbutazone when a patient is presented with musculoskeletal inflammation, such as lameness or joint-related discomfort. It is frequently a point of discussion for horses experiencing chronic conditions like osteoarthritis or acute injuries involving the soft tissues and skeletal system. By managing the biochemical environment associated with tissue stress, your veterinarian can address systemic and localized irritation during the recovery process.

At a pharmacological level, phenylbutazone acts by inhibiting the cyclooxygenase (COX) enzymes, which are responsible for the synthesis of prostaglandins. Prostaglandins are key lipid compounds that mediate the inflammatory response, including the perception of discomfort and the development of localized swelling. By reducing the production of these mediators, phenylbutazone modulates the inflammatory cascade throughout the body. Unlike some newer medications, it is a non-selective inhibitor, meaning it acts on both COX-1 and COX-2 pathways—a factor your veterinarian weighs when designing a long-term management approach. Your veterinarian will determine if phenylbutazone is appropriate for your pet based on their species, weight, health status and the specific nature of the inflammatory challenge.

The actions described here reflect the product's FDA-approved labeling; your veterinarian determines the appropriate use 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.

Commonly observed effects of phenylbutazone include gastrointestinal changes, such as loose stools or a decrease in appetite. Because this medication can influence the protective mucosal lining of the digestive tract and renal blood flow, your veterinarian will monitor for signs of gastric ulcers or changes in kidney function, especially with prolonged use. In horses, right dorsal colitis is a specific clinical concern associated with NSAID administration that owners should watch for. If you observe significant behavioral changes, dark or tarry stools or signs of abdominal discomfort, contact your veterinarian promptly.

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 animals, as its effects on developing offspring are a point of clinical consideration. Because phenylbutazone is highly protein-bound, it can interact with various other prescriptions, including certain anticoagulants and other NSAIDs, so providing your veterinarian with a complete medication history is essential. Your veterinarian will provide specific guidance on administration and may recommend periodic blood work to ensure the protocol remains suitable for your pet's individual health status.