Monural (Fosfomycin Trometamol)

Monural is a phosphonic acid antibiotic indicated for urinary tract infection management and prevention.

• Acute uncomplicated urinary tract infection (uUTI): provides single‑dose eradication of susceptible uropathogens.
• Prophylaxis of recurrent urinary tract infections: reduces the frequency of recurrence in patients with a history of UTIs.
• Urinary tract infection caused by susceptible Gram‑negative bacteria: effective against common pathogens such as Escherichia coli.

• Fosfomycin trometamol inhibits bacterial cell wall synthesis by irreversibly inactivating the MurA enzyme (enolpyruvyl transferase), which catalyzes the first step of peptidoglycan formation. This blockade prevents the construction of a functional cell wall, leading to bacterial lysis and death, particularly in Gram‑negative uropathogens.

Fosfomycin trometamol may cause a range of adverse reactions, most of which are mild and transient.

Common Side Effects

• Nausea: mild to moderate stomach upset.
• Diarrhea: loose stools occurring shortly after dosing.
• Abdominal pain: cramping or discomfort in the lower abdomen.
• Headache: transient mild headache.
• Dyspepsia: indigestion or heartburn.
• Vomiting: occasional emesis.

Serious or Rare Side Effects

• Allergic reactions: rash, pruritus, or anaphylaxis.
• Severe skin reactions: Stevens‑Johnson syndrome or toxic epidermal necrolysis.
• Clostridioides difficile infection: colitis due to bacterial overgrowth.
• Hepatic dysfunction: elevated liver enzymes or hepatitis.
• Renal impairment: worsening kidney function in susceptible individuals.
• Hematologic abnormalities: neutropenia or thrombocytopenia.

Before prescribing Monural, clinicians should consider several safety aspects.

• Assess renal function: dose adjustment may be required in renal impairment.
• Evaluate hypersensitivity: avoid in patients with known fosfomycin allergy.
• Use with caution in pregnancy: classified as Category B, benefits should outweigh risks.
• Monitor liver enzymes: prolonged therapy may affect hepatic function.
• Review concomitant medications: potential interactions may necessitate monitoring.
• Store at below 25°C: keep in the original packaging, protect from moisture and direct sunlight.

Fosfomycin trometamol can interact with other medicines, influencing its absorption or effect.

Major Interactions (Avoid)

• Metoclopramide: reduces fosfomycin absorption; avoid co‑administration.
• Antacids containing aluminum or magnesium: may significantly decrease bioavailability.
• Warfarin: may potentiate anticoagulant effect, increasing INR.

Moderate Interactions (Monitor Closely)

• Diuretics: may increase risk of electrolyte disturbances.
• Probenecid: can raise plasma concentrations of fosfomycin.
• Oral contraceptives: potential reduction in contraceptive efficacy; advise additional contraceptive measures.