DrugABC

UK medicines information — general guidance, not personalised advice.

Clarithromycin

Clarithromycin treats respiratory, skin, and some atypical infections, and is part of some Helicobacter pylori eradication regimens with PPI and amoxicillin or metronidazole. It is not first line for all infections — follow local prescribing guidelines.

This medicine is part of the Antibiotics (selected) category.

Generic name: clarithromycin

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?

    Clarithromycin treats respiratory, skin, and some atypical infections, and is part of some Helicobacter pylori eradication regimens with PPI and amoxicillin or metronidazole.

  • 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?

    Metallic taste, nausea, diarrhoea, or headache.

  • Can you take paracetamol or ibuprofen with it?

    Ask your GP or pharmacist before taking Clarithromycin 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 Clarithromycin is used for

Clarithromycin treats respiratory, skin, and some atypical infections, and is part of some Helicobacter pylori eradication regimens with PPI and Amoxicillin or metronidazole.

It is not first line for all infections — follow local prescribing guidelines.

How does Clarithromycin work, and how long does it take to work?

Macrolides inhibit bacterial protein synthesis.

Complete the prescribed duration.

How and when should you take Clarithromycin?

Tablets with or without food; liquid formulations as measured. Modified-release tablets are swallowed whole.

What are the common side effects of Clarithromycin?

Metallic taste, nausea, diarrhoea, or headache.

Serious side effects of Clarithromycin — when to get urgent help

Seek urgent help for palpitations, fainting, severe diarrhoea after antibiotics (possible C. difficile), or allergic swelling.

What if you miss a dose of Clarithromycin?

Take when remembered unless nearly time for next; do not double.

Who should not take Clarithromycin?

History of QT prolongation with clarithromycin, severe kidney failure without dose adjustment, and some arrhythmia risk profiles.

Can you take paracetamol or ibuprofen with Clarithromycin? — other interactions

Simvastatin and Atorvastatin should be paused or dose-limited during short courses; Warfarin, Digoxin, carbamazepine, Colchicine, and many others interact — pharmacist screening is essential.

Clarithromycin in pregnancy and breastfeeding

Discuss with your prescriber — use if clearly needed.

Blood tests and monitoring on Clarithromycin

ECG in high cardiac risk on longer therapy; INR if on Warfarin.

What might your GP prescribe instead of Clarithromycin?

Azithromycin, erythromycin, or Doxycycline may be substituted depending on infection and interactions.

Reviewed by UK registered pharmacists

Reviewed by UK registered pharmacists for accuracy and clarity. Content is informational only.

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Frequently asked questions about Clarithromycin

People also ask — common Google searches

What is Clarithromycin used for?
Clarithromycin treats respiratory, skin, and some atypical infections, and is part of some Helicobacter pylori eradication regimens with PPI and Amoxicillin or metronidazole. It is not first line for all infections — follow local prescribing guidelines.
How long does Clarithromycin 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 Clarithromycin with paracetamol or ibuprofen?
Ask your GP or pharmacist before taking Clarithromycin 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 Clarithromycin?
Metallic taste, nausea, diarrhoea, or headache. See the sections below for more detail, including serious side effects and when to seek urgent help.
Why stop my statin with clarithromycin?
Levels of some statins rise sharply, risking muscle breakdown — your prescriber tells you when to restart after the antibiotic course.
Can clarithromycin cause a fast heartbeat?
QT prolongation is a recognised risk, higher if you take other QT drugs — report palpitations or fainting.

Need personalised advice?

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Often used with

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