Chlorhexidine is an antiseptic and disinfectant. It helps reduce the number of germs (bacteria) in your mouth or on your skin.

It can help with:

• mouth infections, mouth ulcers and gum disease
• sore throats
• denture care
• skin infections

Chlorhexidine is usually combined with other ingredients. Some sore throat treatments have a local anaesthetic to help numb pain.

Mouth and throat treatments come as mouthwashes, lozenges, gels and sprays.

Skin treatments come as creams, ointments and lotions.

Many chlorhexidine treatments are available to buy in pharmacies, and some in shops and supermarkets.

For nose infections, there is a nasal cream that contains chlorhexidine and neomycin, an antibiotic. This medicine is available on prescription only and is known by the brand name Naseptin.

Chlorhexidine is also used in hospitals and clinics to clean skin or surgical equipment before surgery. It can be used in some bladder procedures, including cleaning catheters.

• You’ll usually use chlorhexidine treatments for up to 4 weeks.
• You’re unlikely to have any side effects with the skin creams and lotions.
• Common side effects with the throat spray, lozenges and dental treatments include a dry mouth and stained teeth.
• When using the lozenges, spray, mouthwash or dental gel, wait at least 30 to 60 minutes before having something to eat or drink. This gives the medicine a chance to work properly.
• Do not use bleach on clothes, bedding or other fabrics that have been in contact with chlorhexidine. It will leave yellowish-brown stains.

Chlorhexidine throat spray, lozenges and dental treatments (including mouthwash and dental gel) can be used by adults and children aged 12 or older.

Chlorhexidine skin treatments can be used by adults and children.

To make sure chlorhexidine is safe for you, tell a pharmacist or doctor before using it if you:

• have ever had an allergic reaction to chlorhexidine or any of the other ingredients
• have ever had an allergic reaction to any other medicine
• cannot drink or need to avoid alcohol. Some chlorhexidine sprays and mouthwashes may contain very small amounts of alcohol. Ask a pharmacist, doctor or dentist about medicines without alcohol.

If you buy a chlorhexidine treatment in a pharmacy or supermarket, follow the instructions that come with it. For prescription medicines, follow the advice from your doctor, dentist or a pharmacist.

Wash your hands before and after using chlorhexidine. Keep it away from your eyes and ears. If chlorhexidine gets into your eyes or ears, rinse well with water.

Dosage and how to use lozenges

The usual dose for children aged 12 and older is up to 5 lozenges a day. Adults can have up to 10 a day.

Put a lozenge in your mouth and let it melt slowly.

Wait at least 30 to 60 minutes before having something to eat or drink.

Dosage and how to use mouthwash

The usual dose is 10 ml, twice a day.

Pour 10ml into the measuring cup. Rinse the mouthwash around your mouth for about 1 minute. Spit out the mouthwash, do not swallow it.

Wait at least 30 to 60 minutes before having something to eat or drink.

Dosage and how to use mouth spray

The usual dose is 2 squirts at a time, up to 12 times a day.

Aim the spray onto your affected tooth, gum, ulcer or the sore part of your mouth.

Wait at least 30 to 60 minutes before having something to eat or drink.

Dosage and how to use throat spray

The usual dose is 3 to 5 squirts. You can repeat this dose up to 10 times a day.

Wait at least 30 to 60 minutes before having something to eat or drink.

How to use dental gel

You’ll usually use the gel once or twice a day.

Put a small amount of gel onto your fingertip or a cotton bud. Gently wipe it across the surface of your mouth ulcer, gum or the sore part of your mouth.

Wait at least 30 to 60 minutes before having something to eat or drink.

How to use sore throat treatments

Only use chlorhexidine lozenges and sore throat spray for a short time. Do not keep using them continuously.

Contact a doctor if your symptoms do not improve after 3 to 4 days.

How to use dental treatments

Use your dental treatment at a different time of day to when you brush your teeth. This is because toothpaste can stop chlorhexidine working properly.

If you cannot use it at a different time, then rinse your mouth thoroughly with water after brushing your teeth. Wait at least 5 minutes before using chlorhexidine.

If your symptoms do not improve after one week, or if they get worse at any time, stop using chlorhexidine and contact your dentist or doctor.

Chlorhexidine treatments are generally very safe. Many people use them without having any side effects at all.

Side effects with skin treatments

There are no common side effects with chlorhexidine skin treatments. However, in rare cases, some people may get red, itchy or irritated skin. It may be because you are using too much lotion or cream where you have folds or creases in your skin, such as around your groin.

Talk to a doctor or pharmacist if this bothers you or does not go away.

Common side effects with sore throat and dental treatments

Some people get peeling skin inside their mouth when using chlorhexidine. If this happens to you, stop using the medicine and the side effect will usually clear up. Speak to your dentist or doctor, who may be able to recommend a different medicine.

Common side effects happen in more than 1 in 100 people. They're usually mild and do not last long.

Talk to a doctor, dentist or pharmacist if these side effects bother you or last for more than a few days:

• dry mouth
• short bursts of a mild burning, tingling or strange taste in your mouth
• your tongue changes colour
• stained teeth

Serious side effects

Stop using chlorhexidine dental treatments and speak to a dentist, doctor or pharmacist if your mouth is:

• sore
• swollen
• irritated
• widespread skin rash

If you have any of the following symptoms, it may be a sign of a more serious infection. Stop using chlorhexidine sore throat treatments and speak to a doctor if you:

• have problems swallowing
• have a severe sore throat
• have had symptoms for more than 2 days
• have a high temperature
• have a headache
• are feeling or being sick (nausea or vomiting)

Stop using chlorhexidine products if you get a widespread skin rash.

Serious allergic reaction

It’s extremely rare to have an allergic reaction (anaphylaxis) to chlorhexidine.

What to do about:

• dry mouth – have sips of water, or try sugar-free gum or sugar-free sweets. If this still bothers you, talk to your doctor, pharmacist or practice nurse They may be able to recommend a spray, gel or lozenges to keep your mouth moist
• mild burning, tingling or strange taste in your mouth – this sometimes happens when you first start treatment but improves as you keep using chlorhexidine. If it does not go away, talk to your doctor about it. It may be an allergy
• your tongue changes colour - this is not permanent and will go when the treatment stops
• stained teeth – make sure you brush your teeth regularly
• skin reactions such as redness, itching and irritation – try using smaller amounts or stop using it completely. Avoid clothes that irritate your skin, such as wool or manmade fabrics. If the skin area is itchy, pat or tap the area rather than scratching

It's generally thought to be OK to use chlorhexidine lozenges or sore throat spray. There's very little information on safety in pregnancy, however, they are not thought to be harmful.

Chlorhexidine and breastfeeding

All chlorhexidine treatments are ok to use while breastfeeding. Although, if chlorhexidine is being used on the skin, make sure the treatment has been washed off from the nipple and breast before feeding.

If you notice that your baby is not feeding as well as usual, or if you have any other concerns about your baby, talk to your health visitor, midwife or doctor as soon as possible.

Chlorhexidine dental, sore throat and skin treatments are not known to cause problems if you take them at the same time as other medicines.

Speak to a doctor or pharmacist if you have any questions.

Mixing chlorhexidine with herbal remedies and supplements

It’s not possible to say whether herbal medicines and vitamins are safe to take with chlorhexidine. They are not tested in the same way as other medicines.