(Tribrissen®, Tucoprim®, Septra® and Bactrim® are other names for this medication.) 

Use: Trimethoprim/sulfa combinations are strong antibiotics used to treat infections in animals.

Side Effects: Some dogs will develop dry eye from sulfa drugs. If your dog starts blinking more, rubbing its eyes or has lots of eye discharge, you should contact your veterinarian immediately. Some animals will develop stomach upset (vomiting and diarrhea) from trimethoprim sulfa combinations. Some animals may develop an arthritis-like condition while on sulfa drugs. Trimethoprim and sulfa drugs can suppress the bone marrow and cause anemia. If you notice fever (103- 105 F) or unusual tiredness in your dog or cat, you should contact your veterinarian.

Precautions: These drugs should probably not be used if your animal has a history of severe anemia. Sulfas should not be used in animals that are dehydrated as stone formation may occur in the kidneys. Always make sure that your pet has plenty of fresh, clean drinking water while on sulfa drugs.

Directions: Dogs and cats usually receive trimethoprim sulfa combinations orally once or twice daily. Cats are repulsed by the taste of trimethoprim sulfa combinations and will salivate profusely if allowed to taste it. Providing trimethoprim sulfa combinations to cats in capsules or other dosage forms that will prevent direct contact with the tongue will make administration of this drug much more pleasant for both the cat and the owner.

Remember: Trimethoprim sulfa combinations should be stored in a tight, light resistant, childproof container away from all children and other household pets. Oral liquids of trimethoprim sulfa should be shaken well before use.

If you miss a dose of this medication you should give it as soon as you remember it, but if it is within a few hours of the regularly scheduled dose, wait and give it at the regular time. Do not double a dose as this can be toxic to your pet.