NITROFURANTOIN

It is a primarily bacteriostatic compound, but may be cidal at higher concentrations and in acid urine its activity is enhanced at lower pH. It inhibits many gram negative bacteria, but due to evelopment of resistance, activity is now restricted largely to E.coli. It antagonizes the action of nalidixic acid.

Indications

Urinary tract infection. Cystitis, pyelitis & pyelonephritis; post-operative infections of urinary tract.

Dosage

50-100 mg 6 hrly with meals. Children : 6 mg/kg bodywt. daily in 4 divided doses.

Contra-Indications

Impaired renal function. Pregnancy, neonates, severe oliguria, anuria.

Special Precautions

Urine turns dark brown on exposure to air. Liver damage & a pulmonary reaction. Concomitant use of Probenecid & Nalidixic acid. Acidify urine. Paediatrics: Contraindicated in under 1 year. Pregnancy: Safety not established. Lactation: Use with caution. May cause anaemia in G6PD deficient infants. Elderly: No special problem.

Side Effects

G.I. intolerance-nausea, diarrhoea. Chills fever & leucopenia. Peripheral neuritis & neurological effects. Haemolytic anaemia.

Drug Interactions

Antagonise Nalidixic acid. Absorbtion reduced by Magnesium trisilicate. Probenecid reduces excretion.Urinary excretion of Pyridoxin increased.