CONTRIBUTOR(S): Vetstream Ltd, Andrea Tarr, Fear Free,
Medication: Trimethoprim-sulfa (sulfonamide)
Medication: Trimethoprim-sulfa (sulfonamide)
Your dog has been prescribed the active ingredient trimethoprim/sulfa to treat a urinary, respiratory tract or prostatic bacterial infection. Sulfa refers to the combination of trimethoprim with a sulfonamide antibiotic (usually sulfadiazine or sulfamethoxazole).
Key points
• Antibiotic.
• Do not use if keratoconjunctivitis or previous history of adverse reaction to sulfonamides or polyarthritis.
• Dosage: twice a day.
This information sheet is designed to help answer commonly asked questions and help you give the medication safely and effectively to your pet. It does not contain all available information for this medication. If you have other questions or need more information, contact your veterinarian or pharmacist.Always follow the dosing instructions provided by your veterinarian.
Name, Brand names, Class of medication and Storage
Name
- Trimethoprim sulfa (Try-meth-oh-prim sul-fa).
Brand name
- Diatrim
- Duphratim
- Norodine
- Trimacare
- Trimedoxine
- Bactrim (US).
Class of medication
- Combination antibiotic product sometimes referred to as a potentiated sulfonamide antibiotic.
Storage
- Store at room temperature (68°F-77°F (20°C-25°C)).
Why has my dog been prescribed trimethoprim?
Your veterinarian may prescribe trimethoprim-sulfa to treat alimentary tract, respiratory, urogenital, skin and wound and eye and ear infections. The combination is sometimes used to treat other types of infection.
Your veterinarian may prescribe trimethoprim alone for urinary, prostatic, systemic salmonella and respiratory tract infections.
How is the medication given?
Trimethoprim in combination with a sulfonamide is given orally as tablets or by injection by your veterinarian.
Are there any side-effects or drug interactions?
Side-effects include:
- Acute hepatitis with vomiting, cholestasis
- Acute pancreatitis
- Immune-mediated thrombocytopenia
- Joint inflammation
- Acute hypersensitivity reactions
- Skin reactions
- Keratoconjunctivitis sicca (KCS) (dry eye)
- May reversibly suppress thyroid function
- Hematological effects
Trimethoprim/sulfonamide combinations should be used with caution in patients with pre-existing hepatic or renal disease. Doberman pinschers appear to be very susceptible to sulfonamide-induced poly-systemic immune complex disease.
If trimethoprim/sulfonamide is given alongside warfarin, the anticoagulant effect of warfarin may be enhanced. The medication can also interact with antacids and the concomitant use with drugs containing procaine should be avoided.
How long will my dog need to receive this medication?
The length of treatment depends on the infection. Your veterinarian may prescribe the medication for a period of 7 days or for 10-14 days.
How should I dispose of this medication if I don’t use it all?
Dispose of any unused trimethoprim safely – don’t flush down the toilet or sink. Ask your veterinary team if they take back medication for disposal. Do not save trimethoprim for future use or give to other pets.
What if I miss a dose or give an extra dose?
If you miss a dose, give the dose as soon as possible but do not double up a dose. Make sure the dose given doesn’t exceed the total recommended amount in any 24-hour period.
My dog is unwell, should I still give the drug?
If your pet is unwell, contact your veterinarian for advice.
What should I do if this medication is accidentally given to another pet or taken by a human?
Trimethoprim-sulfa should only be given to the dog that it has been prescribed for:
- Do not give to other pets in the household
- If accidentally given to other pets, contact your veterinarian for advice.
If accidentally eaten by a human, speak to your primary care physician or poison control center.
Will my dog need to be monitored while on trimethoprim?
As well as checking that the infection is responding, your veterinarian will monitor your dog for any side-effects during treatment with trimethoprim, particularly if the treatment is more long-term. Let your veterinarian know if you notice any side-effects.
Further information
If you have any concerns, further information on trimethoprim can be found on the package insert and the following websites:
Europe & UK
- Veterinary Medicines Directorate (VMD) Diatrim® (Sulfadiazine, Trimethoprim). Website: https://www.vmd.defra.gov.uk/productinformationdatabase/files/QRD_Documents/QRD-Auth_1326523.PDF
- Veterinary Medicines Directorate (VMD) Duphatrim® (Sulfadiazine, Trimethoprim) Injectable. Website: /vmd.defra.gov.uk/productinformationdatabase/files/QRD_Documents/QRD-Auth_1164600.PDF
- Veterinary Medicines Directorate (VMD) Norodine:
USA
- BactrimTM (sulfamethoxazole and trimethoprim) (approved for use in humans): www.accessdata.fda.gov/drugsatfda_docs/label/2013/017377s068s073lbl.pdf
Always follow the recommended dosage and contact your veterinary team or pharmacist if you have any questions regarding your dog’s medication.