Nitrofurantoin
Nitrofurantoin is an antibiotic concentrated in urine, commonly used for uncomplicated lower urinary tract infections when local guidelines support it. It is not used for kidney infections or bloodstream infections in most cases.
This medicine is part of the Antibiotics (selected) category.
Generic name: nitrofurantoin
Quick answers
Short replies to searches people often run before speaking to a clinician. For the overview of what the medicine is used for, see the short summary under the page title above.
What is it for?
Nitrofurantoin is an antibiotic concentrated in urine, commonly used for uncomplicated lower urinary tract infections when local guidelines support it.
How long does it take to work?
Onset varies by condition and dose. Your GP or pharmacist can explain what to expect and when to review.
What are common side effects?
Nausea, vomiting, brown urine discolouration (harmless), or diarrhoea.
Can you take paracetamol or ibuprofen with it?
Ask your GP or pharmacist before taking Nitrofurantoin with paracetamol or ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
More about what Nitrofurantoin is used for
Nitrofurantoin is an antibiotic concentrated in urine, commonly used for uncomplicated lower urinary tract infections when local guidelines support it.
It is not used for kidney infections or bloodstream infections in most cases.
How does Nitrofurantoin work, and how long does it take to work?
It damages bacterial DNA and proteins; resistance patterns vary by region — your prescriber follows local guidance.
Take with food to improve tolerance and absorption.
How and when should you take Nitrofurantoin?
Complete the course even if symptoms improve early unless your prescriber stops it for side effects.
Avoid missing doses to reduce resistance risk.
What are the common side effects of Nitrofurantoin?
Nausea, vomiting, brown urine discolouration (harmless), or diarrhoea.
Serious side effects of Nitrofurantoin — when to get urgent help
Seek urgent help for new chest pain, cough, or breathlessness during or after a course — lung reactions are rare but serious.
Severe allergic reactions or peripheral neuropathy symptoms need prompt review.
What if you miss a dose of Nitrofurantoin?
Take when remembered unless nearly time for next; do not double.
Who should not take Nitrofurantoin?
Significant kidney impairment, G6PD deficiency in some cases, late pregnancy near term, and infants under one month are cautions or contraindications per product information.
Can you take paracetamol or ibuprofen with Nitrofurantoin? — other interactions
Magnesium trisilicate antacids reduce absorption. Few classic broad interactions, but always list all medicines.
Nitrofurantoin in pregnancy and breastfeeding
Avoid near term in pregnancy; discuss breastfeeding with your prescriber.
Blood tests and monitoring on Nitrofurantoin
Long-term prevention doses need periodic review for lung and liver effects.
What might your GP prescribe instead of Nitrofurantoin?
Trimethoprim, fosfomycin, or other antibiotics may be used if nitrofurantoin is unsuitable.
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Reviewed by UK registered pharmacists for accuracy and clarity. Content is informational only.
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Frequently asked questions about Nitrofurantoin
People also ask — common Google searches
- What is Nitrofurantoin used for?
- Nitrofurantoin is an antibiotic concentrated in urine, commonly used for uncomplicated lower urinary tract infections when local guidelines support it. It is not used for kidney infections or bloodstream infections in most cases.
- How long does Nitrofurantoin take to work?
- Onset varies by condition and dose. Your GP or pharmacist can explain what to expect and when to review. Always follow your prescriber’s follow-up plan.
- Can you take Nitrofurantoin with paracetamol or ibuprofen?
- Ask your GP or pharmacist before taking Nitrofurantoin with Paracetamol or Ibuprofen. Many adults use paracetamol for short periods when appropriate; NSAIDs such as ibuprofen need extra checks with your other medicines and health conditions.
- What are the side effects of Nitrofurantoin?
- Nausea, vomiting, brown urine discolouration (harmless), or diarrhoea. See the sections below for more detail, including serious side effects and when to seek urgent help.
- Why is my urine dark on nitrofurantoin?
- Harmless brown discolouration is common. If urine is red with pain, seek medical advice to exclude bleeding.
- Can nitrofurantoin treat kidney infections?
- It does not reach kidney tissue well enough for pyelonephritis in most cases — your GP chooses a different antibiotic if needed.
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