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Septra Dosage

Generic name: TRIMETHOPRIM 80mg, SULFAMETHOXAZOLE 400mg
Dosage form: tablet
Drug class: Sulfonamides

Medically reviewed by Drugs.com. Last updated on Apr 30, 2024.

Contraindicated in pediatric patients less than 2 months of age.

Urinary Tract Infections and Shigellosis in Adults and Pediatric Patients and Acute Otitis Media in Pediatric Patients:

Adults: The usual adult dosage in the treatment of urinary tract infections is one SEPTRA DS (double strength) tablet, two SEPTRA tablets, or four teaspoonfuls (20 mL) SEPTRA Suspension every 12 hours for 10 to 14 days. An identical daily dosage is used for 5 days in the treatment of shigellosis.

Pediatric Patients: The recommended dose for pediatric patients with urinary tract infections or acute otitis media is 8 mg/kg trimethoprim and 40 mg/kg sulfamethoxazole per 24 hours, given in two divided doses every 12 hours for 10 days. An identical daily dosage is used for 5 days in the treatment of shigellosis. The following table is a guideline for the attainment of this dosage:

Pediatric Patients: Two Months of Age or Older
Weight Dose-Every 12 Hours
lb kg Teaspoonfuls Tablets
22 10 1 (5 mL)
44 20 2 (10 mL) 1
66 30 3 (15 mL) 1 1/2
88 40 4 (20 mL) 2 (or 1 DS Tablet)

For Patients With Impaired Renal Function: When renal function is impaired, a reduced dosage should be employed using the following table:




Creatinine Recommended
Clearance Dosage
(mL/min) Regimen
Above 30 Use Standard Regimen
15-30 1/2 the Usual Regimen
Below 15 Use Not Recommended

Acute Exacerbations of Chronic Bronchitis in Adults:

The usual adult dosage in the treatment of acute exacerbations of chronic bronchitis is one SEPTRA DS (double strength) tablet, two SEPTRA tablets, or four teaspoonfuls (20 mL) SEPTRA Suspension every 12 hours for 14 days.

Travelers' Diarrhea in Adults:

For the treatment of travelers' diarrhea, the usual adult dosage is one SEPTRA DS (double strength) tablet, two SEPTRA tablets, or four teaspoonfuls (20 mL) of SEPTRA Suspension every 12 hours for 5 days.

Pneumocystis Carinii Pneumonia:

Treatment:

Adults and Pediatric Patients: The recommended dosage for treatment of patients with documented Pneumocystis carinii pneumonia is 15 to 20 mg/kg trimethoprim and 75 to 100 mg/kg sulfamethoxazole per 24 hours given in equally divided doses every 6 hours for 14 to 21 days. The following table is a guideline for the upper limit of this dosage:

Weight Dose – Every 6 Hours
lb kg Teaspoonfuls Tablets
18 8 1 (5 mL)
35 16 2 (10 mL) 1
53 24 3 (15 mL) 1 1⁄2
70 32 4 (20 mL) 2 (or 1 DS Tablet)
88 40 5 (25 mL) 2 1⁄2
106 48 6 (30 mL) 3 (or 1 1⁄2 DS Tablets)
141 64 8 (40 mL) 4 (or 2 DS Tablets)
176 80 10 (50 mL) 5 (or 2 1⁄2 DS Tablets)

For the lower limit dose (15 mg/kg trimethoprim and 75 mg/kg sulfamethoxazole per 24 hours) administer 75% of the dose in the above table.

Prophylaxis:

Adults: The recommended dosage for prophylaxis in adults is one SEPTRA DS (double strength) tablet daily.

Pediatric Patients: For pediatric patients, the recommended dose is 150 mg/m2/day trimethoprim with 750 mg/m2/day sulfamethoxazole given orally in equally divided doses twice a day, on 3 consecutive days per week. The total daily dose should not exceed 320 mg trimethoprim and 1,600 mg sulfamethoxazole. The following table is a guideline for the attainment of this dosage in pediatric patients:

Body Surface Area Dose–every 12 hours
(m2) Teaspoonfuls Tablets
0.26 1⁄2 (2.5 mL)
0.53 1 (5 mL) 1⁄2
1.06 2 (10 mL) 1

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