Question 1

What is Trimethoprim-Sulfamethoxazole used for?

Accepted Answer

Trimethoprim-Sulfamethoxazole is indicated for: Bacterial infections, chronic skin, coccidia, coccidiosis, General bacterial, Nocardia infections, Pneumocystis (immunocompromised), Pneumocystis pneumonia, prostatitis, Respiratory and GI infections, Respiratory infections, secondary cover, Severe bacterial infection, skin, skin infections, Strep pneumoniae, Susceptible bacterial infections, toxoplasmosis, UTI.

Question 2

What routes can Trimethoprim-Sulfamethoxazole be administered by?

Accepted Answer

Available routes: PO, SC.

Question 3

Which species have cited Trimethoprim-Sulfamethoxazole dosing data?

Accepted Answer

Trimethoprim-Sulfamethoxazole dosing in the ExoticRx formulary covers 12 species: African Grey Parrot, African Pygmy Hedgehog, Bearded Dragon, Cat (Domestic), Cattle (Beef/Dairy), Chinchilla, Dog (Domestic), Ferret, Guinea Pig, Horse (Equine), Pet Rat, Rabbit (Domestic).

Question 4

Is Trimethoprim-Sulfamethoxazole a controlled substance?

Accepted Answer

Trimethoprim-Sulfamethoxazole is not federally scheduled as a controlled substance, but is veterinary prescription only in most jurisdictions.

Question 5

What are the warnings or contraindications for Trimethoprim-Sulfamethoxazole?

Accepted Answer

May cause keratoconjunctivitis sicca (KCS) in dogs with prolonged use. Can cause bone marrow suppression. Avoid in animals with hepatic disease. Adequate hydration required.

Question 6

What are the side effects of Trimethoprim-Sulfamethoxazole?

Accepted Answer

Reported side effects, adverse reactions, and contraindications for Trimethoprim-Sulfamethoxazole: May cause keratoconjunctivitis sicca (KCS) in dogs with prolonged use. Can cause bone marrow suppression. Avoid in animals with hepatic disease. Adequate hydration required.

Question 7

How does Trimethoprim-Sulfamethoxazole work?

Accepted Answer

Sequential blockade of folate synthesis: sulfamethoxazole inhibits dihydropteroate synthase; trimethoprim inhibits dihydrofolate reductase.

Species	Route	Dose	Frequency	Evidence	Source
Dog (Domestic)	SC	15–30 mg/kg	q12h	Moderate	Plumb's Veterinary Drug Handbook, 9th Ed
Dog (Domestic)	PO	15–30 mg/kg	q12h	Strong	Plumb's Veterinary Drug Handbook, 9th Ed

Trimethoprim-Sulfamethoxazole

Drug Class

Routes

Indications

Mechanism of Action

Side effects & warnings

Species with Trimethoprim-Sulfamethoxazole dosing data (24 dose rules)

Evidence levels across 24 dose rules

Backed by 7 published sources

Sample dosing (2 of 24 cited rules)

Upgrade for Full Details