Clavulanic acid: Uses, How It Works, Medicines

Also in: हिन्दी தமிழ் मराठी తెలుగు ಕನ್ನಡ বাংলা ગુજરાતી മലയാളം

Clavulanic acid is a beta-lactamase inhibitor that protects the antibiotic amoxicillin from being destroyed by resistant bacteria. It has very little antibacterial action of its own, so it is used only in combination with amoxicillin, as in co-amoxiclav brands such as Augmentin. The combination is a prescription medicine used to treat certain bacterial infections.

Also known as: Clavulanate, Potassium clavulanate, Clavulanic acid potassium, Amoxicillin clavulanate, Co-amoxiclav, Amoxycillin and clavulanic acid

Pharmacist review in progress. This page is based on the sources listed below and is being checked by our registered pharmacist.

How does Clavulanic acid work?

Many resistant bacteria make beta-lactamase enzymes that break down penicillins such as amoxicillin. Clavulanic acid binds to many of these enzymes and inactivates them, so amoxicillin can go on to kill the bacteria. It is absorbed and cleared quickly, partly through the kidneys and partly by the liver, with a half-life of about an hour.

How to take Clavulanic acid

Clavulanic acid is not sold on its own; it comes fixed together with amoxicillin, and the pack shows both strengths in milligrams. Follow the label or your doctor's advice, and take the course as prescribed. Children's doses are set by a doctor.

Side effects of Clavulanic acid

Clavulanic acid is taken only as part of a combination with amoxicillin, so the side effects below are those of the combination. Stomach and gut effects are the most common.

Uncommon or mild

Diarrhoea or loose stools
Nausea or vomiting (often less likely when taken at the start of a meal)
Thrush: white patches in the mouth, or itching and discharge from the vagina
Indigestion or stomach discomfort
Mild skin rash or itching

Rare but serious: get medical help

Signs of a severe allergic reaction: swelling of the face, lips, tongue or throat, wheezing, difficulty breathing or fainting. Get emergency help immediately
A widespread rash with blisters, peeling skin, or sores in the mouth or eyes
Severe or watery diarrhoea that does not stop, or diarrhoea with blood or mucus, during the course or in the weeks after it
Yellow skin or eyes, dark urine, pale stools or pain in the upper right side of the tummy. Liver problems can appear weeks after the course ends and are thought to be linked mainly to clavulanic acid
Unusual bruising or bleeding, or fits (seizures)

Who should be careful

The warnings below apply to the amoxicillin and clavulanic acid combination. Some people need to check with a doctor before taking it.

Allergy to penicillins, cephalosporins or other antibiotics: the combination must not be taken by people who have had such a reaction
Past jaundice or liver problems after taking amoxicillin with clavulanic acid: it must not be taken again
Liver disease: a doctor may check liver function during treatment
Kidney disease: the dose or number of doses a day may need to change
Glandular fever (infectious mononucleosis): amoxicillin often causes a rash in this viral infection
Pregnancy and breastfeeding: ask your doctor, who will weigh the benefit against any risk
Colds, flu and most coughs and sore throats are caused by viruses, which this antibiotic combination does not treat

Medicines and things that interact with Clavulanic acid

These interactions are those of the amoxicillin and clavulanic acid combination. Tell your doctor or pharmacist about everything you take.

Blood thinners such as warfarin or acenocoumarol: clotting time can change, so extra INR checks may be needed
Methotrexate: penicillins can slow its removal from the body and raise the risk of side effects
Allopurinol (for gout): skin rashes become more likely
Probenecid: raises amoxicillin levels; using them together is generally not recommended
Mycophenolate mofetil (used after organ transplants): its blood level may fall
Combined birth control pills: antibiotics may make them less reliable, and vomiting or severe diarrhoea can stop them being absorbed. Ask your doctor about extra contraception

If someone takes too much

Too much of the amoxicillin and clavulanic acid combination can cause stomach pain, vomiting and diarrhoea. Rarely, very large amounts cause fits or kidney problems. If someone has taken more than prescribed, call 112 or go to the nearest hospital and take the medicine pack with you.

Regulatory status in India

Approved for sale in India only as a fixed combination with amoxicillin, such as Augmentin. This combination is generally a prescription medicine.

Type of medicine

Clavulanic acid belongs to this type of medicine.

Beta-lactamase inhibitors

Medicines that contain Clavulanic acid

These medicines sold in India contain Clavulanic acid. They are listed A to Z, not ranked.

Augmentin 625 Duo · 125 mg film-coated tablet

What is Clavulanic acid used for?

Combination medicines that contain Clavulanic acid are used for these conditions.

Common questions

Why is clavulanic acid added to amoxicillin?

Some bacteria resist amoxicillin by making enzymes that break it down. Clavulanic acid blocks many of these enzymes, so the combination works against a wider range of bacteria than amoxicillin alone. It is not needed for every infection, and a doctor decides which medicine suits it.

Does clavulanic acid cause side effects?

The combination causes diarrhoea more often than amoxicillin alone. Rarely, it causes liver problems such as hepatitis or jaundice, which are thought to be linked mainly to the clavulanic acid part and can appear weeks after the course ends. Report yellow skin or eyes, dark urine or pale stools to a doctor.

Is Augmentin 625 Duo the same as clavulanic acid?

No. Augmentin 625 Duo is a brand whose tablet contains amoxicillin together with clavulanic acid. Clavulanic acid is only one of the two ingredients. Check the strength and ingredient list on the pack, and take it only as prescribed.

Can clavulanic acid be taken without amoxicillin?

It is not sold on its own in India. It has very little antibacterial action by itself and is used to protect amoxicillin. A doctor decides which antibiotic suits an infection, so use the combination only as prescribed.

Does clavulanic acid work on viral infections?

No. The amoxicillin and clavulanic acid combination treats certain bacterial infections only. Colds, flu and most sore throats are caused by viruses and do not respond to it. Your doctor decides whether an antibiotic is needed.

Why does amoxicillin with clavulanic acid cause loose stools?

Antibiotics change the balance of normal bacteria in the gut, and clavulanic acid is linked to diarrhoea more often than amoxicillin alone. Taking it at the start of a meal can help. Tell your doctor if diarrhoea is severe or bloody.

Can alcohol be taken with amoxicillin and clavulanic acid?

Alcohol does not directly stop the combination working, but it can add to nausea and stomach upset, and this medicine can affect the liver. Ask your doctor or pharmacist if you are unsure.

Sources

AUGMENTIN 625 / 1g DUO (amoxycillin and potassium clavulanate tablets IP): prescribing information (revised 16 October 2025). GlaxoSmithKline Pharmaceuticals Limited, India
Amoxicillin Clavulanate. StatPearls, National Center for Biotechnology Information (NCBI), US National Library of Medicine
Amoxicillin-Clavulanate (LiverTox: Clinical and Research Information on Drug-Induced Liver Injury). National Institute of Diabetes and Digestive and Kidney Diseases, via NCBI Bookshelf
Augmentin 625mg Tablets: Summary of Product Characteristics. electronic medicines compendium (emc), UK
Beta-Lactamase Inhibitors. StatPearls, National Center for Biotechnology Information (NCBI), US National Library of Medicine