Trimethoprim with Sulfamethoxazole or Sulfadiazine

General Description: Trimethoprim sulfa is a n oral broad-spectrum antibiotic used in dogs and cats to treat many infections, including protozoal and skin infections. This medication can be given with or without food. Trimethoprim sulfa is available as an o ral paste or suspension, a powder or as tablets.

What is this drug?

Trimethoprim sulfa is a broad-spectrum antibiotic
Trimethoprim sulfa is given by mouth
Reasons for prescribing:

Used to treat many infections, including protozoal and skin infections
Is less likely to cause diarrhea than some antibiotics
What dogs/cats should not take this medication?

Pets with a history of liver disease, anemia or other blood abnormalities
Pets with a history of kidney disease or kidney stones
Dehydrated pets
Pregnant or nursing animals
Pets known to have had an allergic reaction to trimethoprim sulfa or other sulfonamides

Ensure you pet has fresh, clean drinking water at all times.

For liquids, shake well before accurately measuring the dose.

Give this medication with of without food.

Give medication as directed by your veterinarian. This medication is usually given once or twice daily.

Cats don’t like the taste of trimethoprim sulfa and will drool profusely. Providing the drug as a capsule or some other dosage form may facilitate easier administration. After administration, watch the pet closely to ensure the entire dose was consumed

Give the exact amount prescribed and only as often as directed. Missed doses reduce the effectiveness of therapy.

Give this medication for as long as your veterinarian directs. Finish the entire course of treatment.

Ideally, give the medication at the same time daily.

What if dose is missed?

If a dose is missed, give it as soon as you can. If it is time already for the next dose, skip the missed dose and go back to the normal schedule. Do not give two doses at the same time.

What to tell/ask veterinarian before giving medication?

Talk to your veterinarian about:

When will your pet need to be rechecked
What tests may need to be performed prior to and during treatment with this drug
Risks and benefits of using this drug
Tell your veterinarian about:

If your pet has experienced side-effects on other drugs/products
If your pet has experienced digestive upset now or ever
If your pet has experienced liver or kidney disease now or ever
If your pet has experienced any other medical problems or allergies now or ever
All medicines and supplements that you are giving your pet or plan to give your pet, including those you can get without a prescription. Your veterinarian may want to check that all of your pet’s medicines can be given together.
If your pet is pregnant or nursing or if you plan to breed your pet
Storage and Warnings:

Store trimethoprim sulfa in a tight, light resistant, childproof container in a cool, dry place at room temperature away from heat and direct sunlight.

Store liquids in the refrigerator. Discard any unused liquid after 14 days. Shake liquids well before using.

Keep this and all medication out of reach of children and pets. Call your physician immediately if you accidentally take this product.

Pet owners allergic to trimethoprim sulfa and/or other antibiotics should avoid handling this drug.

Potential side effects:

Side effects are rare, but if they occur they can be serious. The following reactions occur not because of the amount of drug given, but the individual pet’s sensitivity to trimethoprim sulfa:

Vomiting, diarrhea, loss of appetite, facial swelling
Joint inflammation (arthritis, fever, muscle soreness), especially in Dobermans
Skin rashes and itchiness
Liver failure (nausea; yellowing of gums, skin, eyes)
Inability to produce adequate tears or ‘dry eye’ (increased blinking or discharge, eye rubbing)
Sulfa bladder or kidney stones
Blood abnormalities (bleeding tendencies, pale gums, fatigue, or fever of 103-105° F)
Dogs can develop hypothyroidism with long-term use
It is important to stop therapy and contact your veterinarian immediately if you think you pet has a medical problem or side effect from this product’s therapy
Can this drug be given with other drugs?

Yes, but possible interactions may occur with antacids, aspirin, blood thinners, glipizide, methotrexate, phenylbutazone, probenecid and thiazide diuretics.
Trimethoprim sulfa should not be used in conjunction with cyclosporine.
Trimethoprim sulfa may interfere with thyroid function testing. If your pet needs to have his thyroid levels checked, you may need to discontinue this medication prior to the test.
If your pet experiences any unusual reactions when taking multiple medications, contact your veterinarian

Contact your veterinarian immediately if pet eats more than the prescribed amount.

What else should I know?

Notify your veterinarian if your animal’s condition does not improve or worsens despite this treatment.

As with all prescribed medicines, trimethoprim sulfa should only be given to the dog/cat for which it was prescribed. It should be given only for the condition for which it was prescribed.

This is just a summary of information about trimethoprim sulfa. If you have any questions or concerns about trimethoprim sulfa or for the condition it was prescribed, contact your veterinarian.

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