Introduction 

Psoriasis is a skin condition that causes red, flaky, crusty patches of skin covered with silvery scales.

These patches normally appear on your elbows, knees, scalp and lower back but can appear anywhere on your body. Most people are only affected in small patches. In some cases, the patches can be itchy or sore.

Psoriasis affects around 2% of people in the UK. It can start at any age, but most often develops in adults under 35 years old. The condition affects men and women equally.

The severity of psoriasis varies greatly from person to person. For some people, it is just a minor irritation, for others it has a major impact on their quality of life.

Psoriasis is a long-lasting (chronic) disease that usually involves periods when you have no symptoms or mild symptoms, followed by periods when symptoms are more severe.

Read more about the symptoms of psoriasis.

When to seek medical advice

You should see your GP if you think you may have psoriasis. They can often diagnose the condition based on the appearance of your skin.

Further tests are usually only necessary if the diagnosis is uncertain, in which case you may be referred to a specialist in skin conditions called a dermatologist.

Read more about diagnosing psoriasis.

Why it happens

Psoriasis occurs when the process by which the body produces skin cells is accelerated. Skin cells are normally made and replaced every three to four weeks, but in psoriasis this process only lasts about three to seven days. The resulting build-up of skin cells is what creates the patches associated with psoriasis.

Although the process is not fully understood, it is thought the increased production of skin cells is related to a problem with the immune system. The immune system is your body's defence against disease and infection, but in people with psoriasis it attacks healthy skin cells by mistake.

As psoriasis can run in families, there is also thought to be a genetic element to psoriasis. However, the exact role that genetics plays in causing psoriasis is unclear.

Many people's psoriasis symptoms start or become worse because of a certain event, known as a trigger. Possible triggers of psoriasis include an injury to your skin, throat infections and using certain medicines.

The condition is not contagious so it cannot be spread from person to person.

Read more about the causes of psoriasis.

Treating psoriasis

There is no cure for psoriasis, but a range of treatments can improve symptoms and the appearance of the affected skin patches.

In most cases, the first treatment used will be a topical treatment, such as vitamin D analogues or topical corticosteroids. Topical treatments are creams and ointments applied to the skin.

If these are ineffective or your condition is more severe, a treatment called phototherapy may be used. Phototherapy involves exposing your skin to certain types of ultraviolet light.

In the most severe cases where other treatments are ineffective, systemic treatments may be used. These are oral or injected medicines that work throughout the whole body.

Find out more about treating psoriasis.

Living with psoriasis

Although psoriasis is just a minor irritation for some people, the condition can sometimes have a significant impact on your life.

For example, some people with psoriasis have low-self esteem due to the affect the condition can have on your physical appearance. It is also quite common for someone with psoriasis to develop tenderness, pain and swelling in the joints and connective tissue. This is known as psoriatic arthritis.

Speak to your GP or healthcare team if you have psoriasis and you have any concerns about your physical and mental wellbeing. They can offer advice and further treatment if necessary. There are also a number of support groups for people with psoriasis, such as The Psoriasis Association, where you can speak to other people with the condition.

Read more about living with psoriasis.

Want to know more?

Psoriasis

Psoriasis is a skin condition that affects around 2% of people in the UK. A skin expert describes the impact psoriasis can have on quality of life and the treatment options available.

Media last reviewed: 04/12/2012

Next review due: 04/12/2014

Page last reviewed: 22/07/2013

Next review due: 22/07/2015