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Sulfamethoxazole Dosage

Applies to the following strengths: 500 mg

Usual Adult Dose for Bacterial Infection

Mild to moderate infections: 2 g orally one time followed by 1 g orally twice a day.
Severe infections: 2 g orally one time followed by 1 g orally 3 times a day.

Usual Adult Dose for Cystitis

2 g orally once, followed by 1 g orally every 6 to 12 hours for 3 to 7 days.

Usual Adult Dose for Inclusion Conjunctivitis

2 g orally one time, followed by 1 g orally every 6 to 12 hours for 21 days.

Usual Adult Dose for Malaria

2 g orally one time, followed by 1 g orally every 8 hours for 7 to 10 days. Used as adjunctive therapy in cases of chloroquine-resistant Plasmodium falciparum.

Usual Adult Dose for Otitis Media

2 g orally one time, followed by 1 g orally every 6-12 hours for 10 to 14 days. Recommend administering in combination with erythromycin or trimethoprim.

Usual Adult Dose for Toxoplasmosis

2 g orally one time, followed by 1 g orally every 8 hours for 2 to 4 months. Should administer with pyrimethamine 75 mg one time followed by 25 mg orally once a day. Folinic acid 3 to 9 mg orally 2 to 3 times a week is recommended to prevent bone marrow toxicity.

Usual Adult Dose for Trachoma

2 g orally once, followed by 1 g orally every 6-12 hours. Therapy should be continued for approximately 21 days, depending on the nature and severity of the infection.

Renal Dose Adjustments

CrCl < 10 mL/min: The usual dose should be administered every 24 hours.

CrCl 10-30 mL/min: The usual dose should be administered every 18 hours.

Liver Dose Adjustments

No adjustment recommended

Precautions

Sulfonamides should be given with caution to patients with impaired renal or hepatic function.

Dialysis

Peritoneal dialysis is not effective and hemodialysis is only moderately effective in eliminating sulfamethoxazole.

Frequently asked questions

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.