Patient information from BMJ

Dandruff

Last published:Nov 23, 2021

Most people get dandruff from time to time. More severe dandruff seems to be linked to yeasts that grow on your scalp. Most anti-dandruff shampoos work by killing these yeasts or stopping them from growing.

You can use our information to talk to your doctor or pharmacist and decide which treatments are best for you.

What is dandruff?

Dandruff is flaky skin on your scalp. Some dandruff is normal, because the top layer of your skin flakes away naturally over time. But dandruff is sometimes caused by a medical condition called seborrheic dermatitis.

Seborrheic dermatitis is a skin condition that causes flaky or inflamed skin. It seems to be linked to yeasts that grow on oily parts of your body, like your scalp or around your nose.

Yeasts are a type of fungus. When seborrheic dermatitis affects your scalp, it can cause large flakes of skin. In young children, this is called "cradle cap." Here, we look only at dandruff caused by seborrheic dermatitis in adults.

What are the symptoms?

Flakes of dandruff caused by seborrheic dermatitis tend to be oily, and they may be a white or yellowish color. You may also get itchy or inflamed skin that looks a bit like a sunburn.

What treatments are available?

Well-known brands of anti-danruff shampoo display the names of the active ingredients clearly on the labels, so it's easy enough to check whether they contain the treatments listed below.

Lots of shampoos are available to help with dandruff. Just washing your hair will help to remove flakes, but anti-dandruff shampoos also contain chemicals to control yeasts or reduce inflammation on your scalp.

Most of these treatments are available over the counter. But some may require a prescription from a doctor, particularly at higher strengths.

Try to avoid getting anti-dandruff shampoos in your eyes, and rinse well with water if you do.

Shampoos and lotions

Most people start off by trying a commonly available anti-dandruff shampoo, such as one that contains pyrithione zinc. 

Other common anti-dandruff shampoos contain coal tar. Some people don't like the smell of tar shampoos, but many products are perfumed to try to reduce this problem.

You could also try a shampoo that contains salicylic acid. Salicylic acid is a chemical that helps to break down hard or scaly skin. 

For more severe dandruff, your doctor may prescribe a shampoo containing ketoconazole. Ketoconazole is a drug that kills funguses, including yeasts. 

Some people find that ketoconazole irritates their scalp. This is more likely if you've recently used a corticosteroid treatment on your skin (see below).

Another treatment that's used for more severe dandruff is selenium sulfide. This is a chemical that helps to kill funguses.

Side effects don't seem to be common with selenium shampoos. But a few people get skin irritation. And some people find the shampoo bleaches their hair slightly or turns their scalp an orange color.

Other treatments for dandruff include shampoos containing either ciclopirox or miconazole. 

If you have dandruff caused by severe dermatitis of the scalp, and other treatments haven't helped, your doctor may suggest using a corticosteroid shampoo or lotion. 

Corticosteroids can have side effects, but using them for a short time shouldn't cause serious problems. Possible side effects include thinning of your skin or slight changes in skin color.

What to expect in the future

Treatment can help get rid of dandruff, but it often comes back. You may need to use your anti-dandruff shampoo again from time to time. You may also be able to use your shampoo regularly to help stop dandruff from coming back. Ask your doctor or pharmacist how often you should be using your treatment.