Trimethoprim-sulfamethoxazole

From IDWiki

Background

  • Sulfonamide antibiotic

Brand Names

  • Septra
  • Bactrim (US)
  • TMP-SMX

Dosing

  • Traditionally based on the trimethroprim component
Form TMP SMX Conversion
Intravenous 16 mg/ml 80 mg/ml 10 mL
Oral suspension 8 mg/ml 40 mg/ml 20 mL
Oral SS tab 80 mg 400 mg 2 tabs
Oral DS tab 160 mg 800 mg 1 tab
  • Resistant Gram-negative infections
    • Cystitis or pyelonephritis: 160 mg/800 mg (1 DS tab) IV/PO q12h
    • Other infections: 8 to 12 mg/kg/day IV/PO divided q8-12h (max 960 mg total daily dose)
  • Nocardia: 10 mg/kg TDD
  • Pneumocystis jirovecii: 15-20 mg/kg TDD
  • CNS infections: 15-20 mg/kg TDD

Oral Dosing

  • Ranges from 1 SS tab BID (160 mg TMP TDD) to 3 DS tabs TID (1440 mg TMP TDD)

Intravenous Dosing

  • 10 to 20 mg/kg TMP total daily dose, split TID to QID
Dose (TMP) Weight (kg) Total dose TMP (mg/day) Dose (IV) Dose (PO)
10 mg/kg 40-49 480 10 mL q8h 1 DS tab q8h
50-64 640 10 mL q6h 1 DS tab q6h, or 2 DS tabs q12h
65-74 720 15 mL q8h 3 SS tabs q8h
75-99 960 15 mL q6h 2 DS tabs q8h, or 3 SS tabs q6h
100-129 1280 20 mL q6h 2 DS tabs q6h
15 mg/kg 40-44 640 10 mL q6h 1 DS tab q6h, or 2 DS tabs q12h
45-49 720 15 mL q8h 3 SS tabs q8h
50-69 960 15 mL q6h 2 DS tabs q8h, or 3 SS tabs q6h
70-79 1200 25 mL q8h 5 SS tabs q8h
80-89 1280 20 mL q6h 2 DS tabs q6h
90-99 1440 30 mL q8h 3 DS tabs q8h
100-109 1600 25 mL q6h 2/2/3/3 DS tabs q6h, or 5 SS tabs q6h
110-119 1680 35 mL q8h 7 SS tabs q8h
120-129 1920 30 mL q6h 3 DS tabs q6h
20 mg/kg 40-54 960 15 mL q6h 2 DS tabs q8h, or 3 SS tabs q6h
55-69 1280 20 mL q6h 2 DS tabs q6h
70-79 1440 30 mL q8h 3 DS tabs q8h
80-89 1600 25 mL q6h 2/2/3/3 DS tabs q6h, or 5 SS tabs q6h
90-104 1920 30 mL q6h 3 DS tabs q6h
105-119 2240 35 mL q6h 3/3/4/4 DS tabs q6h, or 7 SS tabs q6h
120-134 2560 40 mL q6h 4 DS tabs q6h

Renal Dosing

CrCl (mL/min) Bacterial infection (TMP) PJP (TMP)
> 30 8-12 mg/kg/day in 2-4 divided doses 15-20 mg/kg/day in 2-4 divided doses
10 to 29 75% of usual dose 12-15 mg/kg/day in 2-4 divided doses
< 10, including PD Generally not recommended; use 50% of usual dose Generally not recommended; use 7.5-10 mg/kg/day in 2-4 divided doses
Hemodialysis 50% of usual dose, scheduled post-dialysis 50% of usual dose, scheduled post-dialysis
CRRT 7.5 mg/kg/day in 2-4 divided doses 15 mg/kg/day in 2-4 divided doses

Adverse Drug Reactions

Further Reading

  • Considerations when prescribing trimethoprim-sulfamethoxazole. CMAJ. 2011;183(16):1851-1858. doi: 10.1503/cmaj.111152
    • Review of adverse events