Nitrofurantoin

Uncomplicated lower UTIs and prophylaxis of recurrent UTIs.

Nitrofurantoin is reduced by bacterial enzymes to reactive intermediates that damage bacterial DNA, ribosomes and other macromolecules. It achieves high concentrations in urine but low blood levels, which is why it works for bladder infections but not kidney infections or systemic infections.

Women with uncomplicated cystitis. Modified-release (Macrobid) is better tolerated. Not suitable if eGFR is below 45 (inadequate urine concentration). Avoid at term in pregnancy (risk of neonatal haemolysis). Can be used for UTI prophylaxis long-term.

Order online and we review your request. A prescriber checks your consultation form for clinical appropriateness and contacts you if anything else is needed. Once approved, your medication is dispensed and delivered to your door.

Tracked: Tracked delivery, arrives in two working days - Free

When it arrives: Every order is sent tracked. Where this page says in post today, it goes out today. Where it says in post tomorrow, it goes out the next working day. On the rare occasions a medicine is unavailable, we will contact you to talk about timing and alternatives.

We dispense clinically equivalent generic medications where available. Prices shown are for the generic version. If you prefer the branded version, let us know in your order form and we will confirm any price difference.

Nitrofurantoin from £37.99 per course.

Common: diarrhoea, nausea, rash, abdominal discomfort. Amoxicillin/co-amoxiclav: common rash (especially with viral infections). Metronidazole: metallic taste, nausea. Doxycycline: photosensitivity, oesophageal irritation. Rare but serious: Clostridium difficile colitis (persistent diarrhoea), anaphylaxis (penicillins), tendon damage (ciprofloxacin).

Penicillin allergy: do not take amoxicillin, co-amoxiclav, or flucloxacillin. Ciprofloxacin: avoid in tendon disorders, epilepsy, myasthenia gravis. Metronidazole: avoid alcohol during treatment and for 48 hours after. Doxycycline: avoid in children under 12 (teeth staining).

Metronidazole: severe reaction with alcohol (disulfiram-like). Warfarin: many antibiotics alter INR - more frequent monitoring needed. Ciprofloxacin: avoid dairy, calcium, iron, and antacids within 2 hours. Oral contraceptives: no evidence that most antibiotics reduce efficacy (except rifampicin).

Penicillins (amoxicillin, flucloxacillin): generally considered safe in pregnancy and breastfeeding. Metronidazole: avoid in 1st trimester if possible. Doxycycline/lymecycline: contraindicated in pregnancy (teeth/bone effects). Ciprofloxacin: avoid (joint cartilage risk). Nitrofurantoin: avoid at term (neonatal haemolysis). Trimethoprim: avoid in 1st trimester (folate antagonist).

Take with food (improves absorption and reduces nausea). MR version: 100mg twice daily for 3-7 days. Standard: 50mg four times daily. Can turn urine dark yellow/brown (normal). Nausea is common with the standard version. Rare but serious: pulmonary reactions and peripheral neuropathy with long-term use. Not effective for kidney infections.