Category: Pharmacology & Therapeutics
Keywords: Fosfomycin, urinary tract infection, cystitis (PubMed Search)
Posted: 3/3/2018 by Wesley Oliver
Click here to contact Wesley Oliver
Fosfomycin is an antibiotic infrequently used for the treatment of urinary tract infections (UTIs). It has a broad spectrum of activity that covers both gram-positive (MRSA, VRE) and gram-negative bacteria (Pseudomonas, ESBL, and carbapenem-resistant Enterobacteriaceae), which is useful in the treatment of multidrug-resistant bacteria.
Fosfomycin is FDA approved for the treatment of uncomplicated UTIs in women due to susceptible strains of Escherichia coli and Enterococcus faecalis (3g oral as a single dose). Data has also demonstrated that it can be used for complicated UTIs; however, dosing is different in this population (3 g oral every 2-3 days for 3 doses). Fosfomycin is not recommended for pyelonephritis.
The broad spectrum of activity, in addition to only needing a single dose in most cases, makes fosfomycin an attractive option; however, it should be reserved for use in certain circumstances. Fosfomycin should not be considered as a first-line option. It is also more expensive than other medications (~$100/dose) and in countries with high rates of utilization bacteria are developing resistance to fosfomycin. In addition, most outpatient pharmacies do not keep this medication in stock.
Take-Home Point:
Fosfomycin should be reserved for multidrug-resistant UTIs in which other first-line options have been exhausted.
Gupta K, Hooton TM, Naber KG, et al; Infectious Diseases Society of America; European Society for Microbiology and Infectious Diseases. International clinical practice guidelines for the treatment of acute uncomplicated cystitis and pyelonephritis in women: a 2010 update by the Infectious Diseases Society of America and the European Society for Microbiology and Infectious Diseases. Clin Infect Dis. 2011;52(5): e103-e120. doi: 10.1093/cid/ciq257.
Michalopoulos AS, Livaditis IG, Gougoutas V. The revival of fosfomycin. Int J Infect Dis. 2011;15(11):e732-e739. doi: 10.1016/j.ijid.2011.07.007.
MONUROL [prescribing information]. St. Louis, MO: Forest Pharmaceuticals, Inc; 2007. www.accessdata.fda.gov/drugsatfda_docs/label/2008/050717s005lbl.pdf. Accessed 9/7/2017September 7, 2017.
Oteo J, Bautista V, Lara N, et al; Spanish ESBL-EARS-Net Study Group. Parallel increase in community use of fosfomycin and resistance to fosfomycin in extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli. J Antimicrob Chemother. 2010;65(11):2459-2463. doi: 10.1093/jac/dkq346.
Raz R. Fosfomycin: an old—new antibiotic. Clin Microbiol Infect. 2012;18(1): 4-7. doi: 10.1111/j.1469-0691.2011.03636.x
Reffert JL, Smith WJ. Fosfomycin for the treatment of resistant gram-negative bacterial infections. Insights from the Society of Infectious Diseases Pharmacists. Pharmacotherapy. 2014;34(8):845-857. doi: 10.1002/phar.1434.
Vardakas KZ, Legakis NJ, Triarides N, Falagas ME. Susceptibility of contemporary isolates to fosfomycin: a systematic review of the literature. Int J Antimicrob Agents. 2016;47(4):269-285. doi: 10.1016/j.ijantimicag.2016.02.001.
Wankum, Michael, et al. “Fosfomycin Use.” Pharmacy Times, 30 Nov. 2017, www.pharmacytimes.com/publications/health-system-edition/2017/november2017/fosfomycin-use.
