Trimethoprim Dosage
Medically reviewed by Drugs.com. Last updated on Mar 16, 2022.
Applies to the following strengths: 100 mg; 200 mg; 50 mg/5 mL
Usual Adult Dose for:
Usual Pediatric Dose for:
Additional dosage information:
Usual Adult Dose for Urinary Tract Infection
100 mg orally every 12 hours or 200 mg orally every 24 hours
Duration of therapy: 10 days
Use: For the treatment of initial episodes of uncomplicated urinary tract infections due to susceptible strains of Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Enterobacter species, and coagulase-negative Staphylococcus species (including Staphylococcus saprophyticus)
Usual Pediatric Dose for Urinary Tract Infection
12 years or older: 100 mg orally every 12 hours or 200 mg orally every 24 hours
Duration of therapy: 10 days
Use: For the treatment of initial episodes of uncomplicated urinary tract infections due to susceptible strains of E coli, P mirabilis, K pneumoniae, Enterobacter species, and coagulase-negative Staphylococcus species (including S saprophyticus)
Usual Pediatric Dose for Otitis Media
6 months or older: 5 mg/kg orally every 12 hours for 10 days
Maximum dose: 200 mg/dose
Comments:
-This drug is not indicated for prophylactic or prolonged use in otitis media at any age.
-When infection with Moraxella catarrhalis suspected, use of alternative antimicrobial agents should be considered.
Use: For the treatment of acute otitis media due to susceptible strains of Streptococcus pneumoniae and Haemophilus influenzae
Renal Dose Adjustments
CrCl 15 to 30 mL/min:
-Oral solution: Usual dose should be reduced by 50%.
-Tablets: 50 mg orally every 12 hours
CrCl less than 15 mL/min: Not recommended.
Liver Dose Adjustments
Caution recommended.
Precautions
CONTRAINDICATIONS:
-Hypersensitivity to the active component or any of the ingredients
-Documented megaloblastic anemia due to folate deficiency
Safety and efficacy have not been established in patients younger than 2 months.
-Oral solution: Efficacy in the treatment of acute otitis media has not been established in patients younger than 6 months.
-Tablets: Efficacy of this drug as a single agent has not been established in patients younger than 12 years.
Consult WARNINGS section for additional precautions.
Dialysis
Data not available
Comments:
-Peritoneal dialysis is not effective and hemodialysis is only moderately effective in eliminating this drug.
Other Comments
Storage requirements:
-Oral solution: Store between 15C to 25C (59F to 77F); protect from light.
-Tablets: Store at 20C to 25C (68F to 77F).
General:
-To reduce the development of drug-resistant organisms and maintain effective therapy, this drug should be used only to treat or prevent infections proven or strongly suspected to be caused by susceptible bacteria.
-Culture and susceptibility information should be considered when selecting/modifying antibacterial therapy or, if no data are available, local epidemiology and susceptibility patterns may be considered when selecting empiric therapy.
-Cultures and susceptibility tests should be performed to determine susceptibility to this drug; therapy may be started before test results are known.
Monitoring:
-Hematologic: Complete blood counts (if any clinical signs of blood disorders)
-Metabolic: Potassium levels in elderly patients
-Renal: Renal function (by calculating CrCl) in elderly patients
Patient advice:
-Avoid missing doses and complete the entire course of therapy.
-Consult physician at once if watery and bloody stools (with or without stomach cramps and fever) develop.
Frequently asked questions
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