Nitrofurantoin Strandhaven T/A Somex Pharma (Nitrofurantoin)

Nitrofurantoin is a nitrofuran antibiotic used to treat infections of the urinary tract caused by susceptible bacteria.

• Uncomplicated urinary tract infection: reduces bacterial load and resolves infection symptoms in adult patients.
• Recurrent urinary tract infection prophylaxis: helps prevent recurrence in individuals with a history of susceptible infections.
• Acute cystitis: provides bactericidal activity to clear infection of the bladder lining.

• Nitrofurantoin is reduced by bacterial flavoproteins to reactive intermediates that damage bacterial DNA, ribosomal proteins, and enzymes involved in carbohydrate metabolism. This multi‑targeted attack interferes with essential cellular processes, leading to rapid bactericidal activity against susceptible urinary pathogens while achieving high concentrations in the urine.

Nitrofurantoin may cause a range of adverse reactions, most of which are mild and reversible.

Common Side Effects

• Nausea: mild to moderate upset stomach.
• Vomiting: occasional episodes of emesis.
• Loss of appetite: reduced desire to eat.
• Diarrhea: loose stools.
• Headache: transient cranial discomfort.
• Metallic taste: altered taste perception.

Serious or Rare Side Effects

• Pulmonary toxicity: interstitial lung disease or acute respiratory distress.
• Hepatic injury: elevated liver enzymes or hepatitis.
• Hemolytic anemia: especially in patients with G6PD deficiency.
• Severe allergic reactions: rash, angioedema, or anaphylaxis.
• Peripheral neuropathy: numbness or tingling in extremities.
• Acute kidney injury: reduced renal function in susceptible individuals.

Before prescribing Nitrofurantoin, clinicians should consider several safety factors.

• Renal function: assess creatinine clearance and avoid use in patients with markedly reduced renal function.
• Pregnancy: avoid use in late pregnancy due to risk of fetal hemolysis and neonatal complications.
• G6PD deficiency: contraindicated because of potential hemolytic anemia.
• Drug interactions: review concomitant medications for potential absorption or toxicity issues.
• Patient counseling: advise completion of the full prescribed course even if symptoms improve.
• Store at ambient temperature: keep below 25°C in the original packaging, protect from moisture.

Nitrofurantoin may interact with other medicines, requiring attention to avoid reduced efficacy or increased toxicity.

Major Interactions (Avoid)

• Antacids containing magnesium or aluminum: decrease nitrofurantoin absorption.
• Cimetidine: may increase nitrofurantoin plasma concentrations.
• Probenecid: can raise nitrofurantoin levels, increasing toxicity risk.
• Warfarin: may potentiate anticoagulant effect and raise INR.
• Methenamine: antagonistic effect on urinary antibacterial activity.

Moderate Interactions (Monitor Closely)

• Fluoroquinolones: additive risk of tendonitis or tendon rupture.
• High-dose vitamin C: may alter urinary pH and affect drug activity.
• Diuretics: can affect renal clearance of nitrofurantoin.
• Sulfonamides: overlapping toxicity profiles, especially hypersensitivity.
• Beta‑lactam antibiotics: may increase risk of hypersensitivity reactions when combined.