Description

Fosfomycin has in vitro activity against a broad range of gram-positive and gram-negative aerobic microorganisms, associated with uncomplicated urinary tract infections. Fosfomycin Trometamol is a phosphonic acid derivative. It is a synthetic, broad spectrum, bactericidal antibiotic for oral administration. The bactericidal action of Fosfomycin is due to its inactivation of the enzyme enolpyruvyl transferase, thereby irreversibly blocking the condensation of uridine diphosphate N-acetylglucosamine with p-enolpyruvate, one of the first steps in bacterial cell wall synthesis.

When Fosfomycin is coadministered with metoclopramide, which increases gastrointestinal motility, lowers the serum concentration and urinary excretion of fosfomycin. Other drugs that increase gastrointestinal motility may produce similar effects.

Fosfomycin is contraindicated in patients with known hypersensitivity to the drug and patients with severe renal insufficiency and patients undergoing haemodialysis.

In clinical trials, the most frequently reported adverse events occurring in >1% of the study population regardless of drug relationship were: diarrhea 10.4%, headache 10.3%, vaginitis 7.6%, nausea 5.2%, rhinitis 4.5%, back pain 3.0%, dysmenorrhea 2.6%, pharyngitis 2.5%, dizziness 2.3%, abdominal pain 2.2%, pain 2.2%, dyspepsia 1.8%, asthenia 1.7%, and rash 1.4%.The following adverse events occurred in clinical trials at a rate of less than 1%, regardless of drug relationship: abnormal stools, anorexia, constipation, dry mouth, dysuria, ear disorder, fever, flatulence, flu syndrome, hematuria, infection, insomnia, lymphadenopathy, menstrual disorder, migraine, myalgia, nervousness, paresthesia, pruritus, SGPT increased, skin disorder, somnolence, and vomiting.

Fosfomycin is pregnancy category B. This drug should not be used during pregnancy unless the benefit outweighs the risk. A decision should be made to discontinue breastfeeding or to not administer the drug, taking into account the importance of the drug to the mother.

Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including Fosfomycin. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile. Do not use more than one single dose of Fosfomycin to treat a single episode of acute cystitis. Repeated daily doses of Fosfomycin did not improve the clinical success or microbiological eradication rates compared to single dose therapy, but did increase the incidence of adverse events.

When Fosfomycin is coadministered with metoclopramide, which increases gastrointestinal motility, lowers the serum concentration and urinary excretion of fosfomycin. Other drugs that increase gastrointestinal motility may produce similar effects.