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What is psoriasis and what causes it?

Have you developed rough, red patches on your skin? You may be experiencing a common condition known as psoriasis.

About psoriasis

Psoriasis is a skin condition that causes patches of scaly, flaky and red skin to develop across the body. It’s thought to affect 2% of people in the UK.* While it can develop at any age, most people begin to experience symptoms before the age of 35.

Psoriasis is a chronic condition, which means most people live with it on a long-term basis. Typically you will experience flare-ups followed by periods where your skin appears to be fine. There is no cure for psoriasis, but there are plenty of treatments available that may help you to manage your symptoms.

Psoriasis causes

The causes of psoriasis are not fully understood, but it’s thought to be related to the immune system. Essentially, in people with psoriasis, skin cells are produced and replaced more quickly than in other people.

It’s important to note that psoriasis is not a condition caused by bad hygiene or dry skin – although keeping the skin moisturised may help ease symptoms. Psoriasis is also not a contagious condition, which means you can’t catch it from anyone, or pass it on.

Your immune system

New skin cells are produced beneath the skin and normally rise to the surface, where they die and flake off. This happens over a period of three to four weeks.**

In people with psoriasis, this process takes place over a matter of days, which leads to immature skin cells accumulating rapidly on the surface of the skin. This build-up causes the red, raised, flaky and scaly appearance of psoriasis.

It’s thought that this process is activated by the immune system mistakenly attacking healthy skin, causing the skin to rapidly produce new cells.

Your genetics

You’re more likely to experience psoriasis symptoms if the condition runs in your family. It’s thought that many different genes contribute to psoriasis, but that possessing these genes is not a guarantee you will develop the condition.

Your triggers

Once you have developed psoriasis you may start to notice that certain things trigger your symptoms.

Common psoriasis triggers include:

  • An injury to the skin
  • Stress
  • Smoking
  • Drinking a lot of alcohol
  • Hormonal changes
  • Certain medicines, such as lithium and ibuprofen
  • A throat infection
  • Conditions that affect the immune system, such as HIV

Where possible, identify your triggers and they try to avoid your triggers as this will help you avoid bad flare-ups of symptoms.

Psoriasis types and symptoms

There are several different types of psoriasis, all of which have slightly different symptoms.

Most people have plaque psoriasis, which is where distinctive raised patches (known as plaques) develop across the body. These plaques appear red and rough with silvery scales. For some people these plaques can be very itchy and sore.

Commonly, people who have plaque psoriasis will also experience scalp psoriasis – in other words they will develop plaques on their head, beneath their hair. A key feature of scalp psoriasis is that it causes flaking similar to dandruff. Occasionally it can also lead to temporary hair loss.

Guttate psoriasis is a variety of the condition characterised by small, teardrop-shaped patches of sore skin developing on the body – normally the chest, arms, legs and/or scalp. This type of psoriasis is most common in children, teenagers and young adults, and can often occur after a throat infection.

Nail psoriasis presents very differently to other varieties. It can affect the fingernails and toenails, and causes discolouration, crumbling, splitting, and dents to appear in the surface of the nail. Sometimes the nail can separate completely from the nail bed.

Inverse or flexural psoriasis is psoriasis that affects the folds and creases in the skin. When affected by psoriasis the skin in these regions does not appear dry and scaly, but rather bright red and shiny. Because it looks different to plaque psoriasis, it may be mistaken for a skin infection.

Pustular psoriasis is where fluid-filled yellow or white blisters develop on the skin. They are typically surrounded by red, dry and flaky patches of skin that may crack. When the pustules burst they can turn brown in colour and develop a crust.

Erythrodermic psoriasis is psoriasis that affects the skin on the entire body, causing intense and widespread itching, burning and soreness.

If you’re concerned about your skin symptoms and you think you may be experiencing psoriasis, make an appointment with your GP.