Adjustment of Dose & Administration
Indication-Specific Adjustment
- Uncomplicated UTI in women 18 years and older:
- Single 3 g dose with or without food
- Complicated UTI (unlabeled): Males: Oral:
- 3 g every 2-3 days for 3 doses
- Prostatitis (unlabeled): Males: Oral:
- 3 g every 3 days for a total of 21 days
Renal Adjustment
No dosage adjustment provided in manufacturer’s labeling
In 5 anuric patients undergoing hemodialysis, the t1/2 of fosfomycin during hemodialysis was 40 hours. In patients with varying degrees of renal impairment (creatinine clearances varying from 54 mL/min to 7 mL/min), the t1/2 of fosfomycin increased from 11 hours to 50 hours. The percent of fosfomycin recovered in urine decreased from 32% to 11% indicating that renal impairment significantly decreased the excretion of fosfomycin.
Drug-Specific Information
Pour sachet contents into 3 to 4 ounces of water and stir; do not use hot water
Administer immediately after dissolving in water
Restricted Use
Use of fosfomycin is restricted to ID telephone approval.
General Notes
- Up-to-date cost information, click here
- IV antimicrobials outpatient (OPAT) dosing, click here
- Obesity dosing weight recommendations here
- Helpful drug-drug interaction check website here
- When dosing guidance is provided it is important to note the following:
Fixed (ie non weight-based) doses in adults are historically based on a 70 kg patient. Specific disease states or individual patients may warrant dosages that differ from the above recommendations. Since product-specific criteria for dose adjustment based on creatinine clearance exist, consult product information regarding specific recommendations for dosage adjustment based on estimated creatinine clearance.