From the Guidelines
Fosfomycin is a recommended treatment option for uncomplicated urinary tract infections (UTIs) in women, particularly when a simple, one-dose treatment is desired, as stated in the 2021 guidelines from the American College of Physicians 1.
Key Points to Consider
- Fosfomycin should be considered for patients with symptoms of a lower UTI, such as burning with urination, frequency, or urgency, and who want convenient treatment with minimal side effects.
- It is particularly useful for patients with allergies to other antibiotics, pregnant women, or those who have had previous UTIs caused by resistant bacteria.
- The standard dosage is one 3-gram packet of powder dissolved in water and taken by mouth just once, preferably on an empty stomach in the evening after emptying the bladder and before going to bed.
- Fosfomycin works by inhibiting bacterial cell wall synthesis and achieves high concentrations in the urine for 1-3 days after a single dose, making it effective against most common UTI pathogens, including E. coli.
Important Considerations
- Fosfomycin may not be appropriate for upper urinary tract infections (pyelonephritis), complicated UTIs, or severe infections requiring hospitalization.
- Common side effects include diarrhea, headache, and nausea, but these are usually mild.
- The guidelines from the Infectious Diseases Society of America (IDSA) and the European Society for Microbiology and Infectious Diseases (ESCMID) support the use of fosfomycin as a single dose for uncomplicated cystitis in women 1.
Summary of Recommendations
- Fosfomycin is a viable option for uncomplicated UTIs in women, offering a convenient, one-dose treatment with minimal side effects.
- It is essential to consider the patient's medical history, including allergies and previous UTIs, when deciding on fosfomycin as a treatment option.
- Fosfomycin should be used in accordance with the recommended dosage and administration guidelines to maximize its effectiveness and minimize potential side effects.
From the FDA Drug Label
The recommended dosage for women 18 years of age and older for uncomplicated urinary tract infection (acute cystitis) is one sachet of fosfomycin tromethamine granules for oral solution. Fosfomycin tromethamine granules for oral solution is indicated only for the treatment of uncomplicated urinary tract infections (acute cystitis) in women due to susceptible strains of Escherichia coli and Enterococcus faecalis. Do not use more than one single dose of fosfomycin tromethamine to treat a single episode of acute cystitis.
You should consider using fosfomycin one treatment one time for uncomplicated urinary tract infection (acute cystitis) in women 18 years of age and older, due to susceptible strains of Escherichia coli and Enterococcus faecalis 2, 2, 2.
From the Research
Fosfomycin Treatment for UTI
- Fosfomycin is a recommended first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis in otherwise healthy adult nonpregnant females, particularly for a 3-g single dose of fosfomycin tromethamine 3.
- The efficacy of fosfomycin has been compared to other antibiotics, such as nitrofurantoin, in the treatment of uncomplicated UTI, with no significant differences in clinical and microbiological cure rates found within 4 weeks of treatment 4.
- A single dose of fosfomycin has been shown to have equal efficacy and tolerability as a five-day course of ciprofloxacin in the treatment of simple urinary infections 5.
Considerations for Fosfomycin Use
- Fosfomycin is an alternative first-line agent for the treatment of acute uncomplicated UTI, particularly in cases where there is increasing resistance to traditional antibiotics such as trimethoprim-sulfamethoxazole 6.
- The selection of fosfomycin as a treatment option should consider factors such as pharmacokinetics, spectrum of activity, resistance prevalence, potential for adverse effects, and duration of therapy 6.
- Fosfomycin has been compared to nitrofurantoin in female patients with uncomplicated UTI, with comparable bacteriologic and clinical cure rates observed 7.
Special Considerations
- Fosfomycin may be a useful treatment option for UTIs caused by multidrug-resistant organisms, including ESBL-producing Enterobacteriales and carbapenem-resistant Enterobacteriales 3.
- The use of fosfomycin should be guided by local susceptibility patterns and the patient's medical history, including any previous exposure to antibiotics 3.