Pityriasis versicolor

About pityriasis versicolor

The patches caused by pityriasis versicolor may be darker or lighter than your normal skin colour, or may be red, brown or pink.

They tend to develop gradually and may join up to form larger patches over time.

The areas most often affected by pityriasis versicolor include the back, chest, upper arms, neck and tummy.

Although it may look unpleasant and the patches are sometimes itchy, pityriasis versicolor is harmless.

You may still want to see your GP, as it usually only improves with treatment. They can normally diagnose pityriasis versicolor by examining your skin.

Why it happens

Pityriasis versicolor is caused by a type of yeast called Malassezia. This yeast is found on the skin of more than 90 per cent of adults, where it normally lives without causing any problems.

But pityriasis versicolor can develop if this yeast starts to multiply more than usual. It's not clear exactly why this happens in some people and not in others.

Several factors can increase your risk of developing pityriasis versicolor, including:

• being in a warm, moist environment (Northern Ireland, in the summertime, can be warm enough)
• sweating excessively (hyperhidrosis)
• creams, dressings or clothing that don't allow your skin to breathe
• being malnourished
• having a weakened immune system
• being a teenager or in your early 20s

Pityriasis versicolor isn't related to poor hygiene. The condition can't be spread from person to person because most people already have the Malassezia yeast on their skin.

How pityriasis versicolor is treated

Pityriasis versicolor can be treated with antifungal medicines. These are available as shampoos, creams and tablets. Your GP will help you decide what treatment is best for you.

Antifungal shampoos

Antifungal shampoos are often the first treatment recommended for pityriasis versicolor.

These are available to buy over the counter from pharmacies, or your GP can prescribe them.

Ask your pharmacist if you need more information about treating the condition.

Antifungal creams

If only small areas of skin are affected, your GP may prescribe an antifungal cream. These creams usually need to be applied to the affected area of skin once or twice a day for several weeks.

Some people experience a burning sensation when they use these antifungal creams, but this is uncommon.

Antifungal tablets

If a large area of skin is affected or other treatments haven't helped, you may be prescribed antifungal tablets by your GP.

Side effects of these tablets are uncommon, although some people experience problems such as rashes, feeling sick and abdominal (tummy) pain while taking them.

Outlook

Overall, antifungal shampoos, creams and tablets are effective in killing the yeast that causes pityriasis versicolor.

But it can take several weeks or months for your skin to return to its normal colour. In more persistent cases, treatment may need to be repeated.

Recurrences

It's common for pityriasis versicolor to come back after treatment. This is particularly during the summer or during holidays to warm and humid countries.

But you can reduce this likelihood by regularly using the antifungal shampoos mentioned above.

For example, using the shampoo once a day for a few days before going on holiday can help prevent pityriasis versicolor recurring.

As these shampoos are available to buy from pharmacies, you don't need to see your GP for a prescription if you run out.

If you develop pityriasis versicolor again after treatment, you can try treating it yourself with antifungal shampoo or see your GP for advice and alternative treatments.

If you have frequent and severe episodes of pityriasis versicolor, your GP may consider prescribing antifungal tablets to take a few times a month to prevent the condition recurring.

They may also refer you to a skin specialist called a dermatologist.

Differences between pityriasis versicolor and vitiligo

Pityriasis versicolor can sometimes be confused with vitiligo, as they both cause the skin to become discoloured in patches.

But there are ways to tell the difference:

• vitiligo often develops symmetrically (on both sides of your body at the same time), while pityriasis versicolor may not
• skin affected by vitiligo usually has a normal texture, while areas affected by pityriasis versicolor are usually slightly scaly or flaky
• vitiligo is more common around the mouth, eyes, fingers, wrists, armpits and groin, while pityriasis versicolor tends to develop on the back, chest, upper arms, neck and tummy

• Read more about vitiligo

More useful links

• How to use your health services