About psoriasis

While no cure has yet been found, nowadays there are many options for treatment for psoriasis to help you manage your symptoms. Don't lose heart if one treatment doesn't work for you - different treatments work in different ways and just because one treatment fails it doesn't mean they all will. The chances are you'll be able to get the symptoms under control and lead a perfectly normal life.

Some people with psoriasis develop a form of arthritis called psoriatic arthritis. Like other forms of arthritis this causes pain and swelling in the joints. Psoriatic arthritis can happen many years after the skin symptoms appear, although some people get the skin symptoms later or at the same time as the joint pain. Psoriatic arthritis can lead to permanent joint damage, but treatments can help stop joint damage from progressing - so it's important to see your doctor if you think you may have arthritis.

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Types of psoriasis

There are lots of different types of psoriasis which all look slightly different, although red and inflamed skin is common in all of them. The different types of psoriasis may need different treatments.

1. Plaque psoriasis

   This is the most common type of psoriasis – 90% of people who have psoriasis have this type. Plaque psoriasis is so called because patches or lesions of red skin known as ‘plaques’ form on the skin. Varying in size and thickness, they tend to affect the knees, elbows, scalp, hairline, and lower back. Silvery-white scales or flakes can also develop. Sometimes the patches can bleed if you knock or scratch your skin.

2. Guttate psoriasis

   This causes a widespread rash of small, scaly spots usually on your stomach, arms and legs. They look like they’ve been scattered like raindrops; indeed, guttate psoriasis is sometimes known as ‘tear drop’ or ‘raindrop’ psoriasis. You may have several patches which are small (often less than 1cm in diameter) and scaly.

3. Erythrodermic psoriasis

   This is a rare and more serious form of psoriasis in which skin redness (also called ‘erythema’) can affect your whole body. This type of psoriasis can sometimes be life-threatening. It may evolve from plaque psoriasis, or may be a response to topical therapy (creams and ointments).

4. Pustular psoriasis

   This causes small yellow-brown pus spots on the palms of your hands and the soles of your feet (called palmoplantar pustulosis).

5. Generalised pustular psoriasis

   Also called von Zumbusch psoriasis, this is a rare and serious form of psoriasis where the skin becomes covered with pustules. It can happen very suddenly and very quickly.

Why do I have psoriasis?

No-one knows exactly what causes psoriasis. But we do know it's an auto-immune disease. This means that your immune system - which protects you from infections and disease - attacks healthy cells instead. In the case of psoriasis, the immune system acts against skin cells, sending out faulty signals that speed up the growth cycle of skin cells. This causes the redness (inflammation) and makes the cells divide much faster than normal. Your skin usually takes around 28 days to renew and replace itself but in areas affected by psoriasis, this process speeds up to around 3 or 4 days. The old skin cells don't have time to shed in the normal way and the new skin cells don't mature properly - so creating the thick patches of psoriasis.

The red appearance of psoriasis plaques can also be because of an increase in the number of blood vessels to the skin and this is why your psoriasis patches can sometimes bleed.

So what brings on this auto-immune response? And why do some people get psoriasis and others don't? The exact lead-up to psoriasis remains a mystery, but it's thought that there are several factors at work - for example, the genes we inherit from our parents seem to play a role in deciding whether we develop Psoriasis. About a third of people with Psoriasis have a close relative with the condition. But genes are not wholly to blame. It seems that other things going on in our daily lives can also contribute. You may find that yours gets worse if you're feeling stressed, for instance. Alcohol, smoking and some medicines (such as lithium and beta-blockers) can also bring on flares in psoriasis.