Nitrofurantoin Glenmark Pharmaceuticals Europe (Nitrofurantoin)

Nitrofurantoin belongs to the nitrofuran antibiotic class and is used to manage infections of the urinary tract.

• Uncomplicated urinary tract infections: eradicates common urinary pathogens and relieves infection symptoms.
• Acute cystitis: provides rapid bactericidal activity against causative organisms in bladder infection.
• Prophylaxis of recurrent urinary tract infections: reduces the frequency of repeat infections when used as a preventive regimen.

• Nitrofurantoin is reduced by bacterial flavoproteins to reactive intermediates that damage bacterial DNA, ribosomal proteins and enzymes involved in carbohydrate metabolism. This multi‑target inhibition leads to bactericidal activity, particularly against common urinary pathogens such as Escherichia coli, Enterococcus spp., and Staphylococcus saprophyticus.

Adverse reactions to Nitrofurantoin may vary in frequency and severity.

Common Side Effects

• Nausea: mild to moderate upset stomach often occurring early in therapy.
• Loss of appetite: reduced desire to eat during treatment.
• Headache: transient cranial discomfort reported by some patients.
• Diarrhoea: loose stools that usually resolve after continued dosing.

Serious or Rare Side Effects

• Pulmonary toxicity: interstitial lung disease or acute respiratory distress, requiring immediate medical attention.
• Hepatic injury: elevated liver enzymes or hepatitis, potentially severe.
• Hemolytic anemia in G6PD deficiency: rapid destruction of red blood cells leading to jaundice and fatigue.

When prescribing Nitrofurantoin, clinicians should consider several safety aspects.

• Renal function: assess creatinine clearance before initiating therapy to ensure adequate drug excretion.
• G6PD deficiency: avoid use due to risk of hemolytic anemia.
• Pregnancy: limit use to situations where benefits outweigh potential fetal risks, especially in the first trimester.
• Elderly patients: monitor for signs of pulmonary toxicity and adjust dosing if needed.
• Drug interactions: avoid concomitant use with antacids containing magnesium or aluminium, which can impair absorption.
• Store at below 25°C: keep in the original packaging, protect from moisture and direct sunlight.

Nitrofurantoin may interact with other medicines, altering its efficacy or safety profile.

Major Interactions (Avoid)

• Antacids containing magnesium or aluminium: reduce oral absorption of Nitrofurantoin.
• Probenecid: increases plasma concentrations, raising toxicity risk.
• Warfarin: may potentiate anticoagulant effect, requiring closer INR monitoring.

Moderate Interactions (Monitor Closely)

• NSAIDs: combined use can increase risk of renal impairment.
• Diuretics: may affect renal clearance and drug levels.
• Oral contraceptives: possible reduction in contraceptive effectiveness, advise additional contraceptive measures.