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Fosfomycin Dosage

Applies to the following strengths: 3 g

The information at is not a substitute for medical advice. Always consult your doctor or pharmacist.

Usual Adult Dose for Cystitis

3 g (1 sachet) orally once as a single dose

-This drug should not be used for the treatment of pyelonephritis or perinephric abscess.

Use: For the treatment of uncomplicated urinary tract infections (acute cystitis) in women due to susceptible strains of Escherichia coli and Enterococcus faecalis

Usual Adult Dose for Transurethral Prostatectomy

3 g (1 sachet) orally on the evening before the procedure and then 3 g orally on the evening after the procedure

-Not approved by US FDA.

Renal Dose Adjustments

Data not available

Liver Dose Adjustments

Data not available


Safety and efficacy have not been established in patients younger than 12 years; only approved for use in women 18 years or older.

Consult WARNINGS section for additional precautions.


Data not available

Other Comments

Administration advice:
-May take with or without food
-Do not take this drug in its dry form; always mix with water prior to ingestion; take immediately after dissolving in water.

Reconstitution/preparation techniques:
-The contents of 1 sachet should be dissolved in 3 to 4 ounces of water (1/2 cup) immediately prior to administration; hot water should not be used.

-Urine specimens for culture and susceptibility testing should be obtained before and after oral therapy.
-If bacteriuria persists or reappears after use of this drug, alternative therapeutic regimens should be selected based on microbiological studies.

Patient advice:
-If symptoms do not improve in 2 to 3 days after taking the single oral dose, contact healthcare provider promptly.