Psoriasis

Psoriasis is a skin condition that typically causes raised patches of red, scaly skin – these patches are called plaques. Symptoms tend to come and go over time. There’s no cure for psoriasis. But there are lots of treatments and things you can do to help manage your symptoms.

About psoriasis

If you have psoriasis, your skin makes new cells faster than normal. These cells build up on your skin, causing thick, red, crusty patches. Your skin may also become inflamed.

Psoriasis symptoms usually come and go. Sometimes you’ll have no symptoms or hardly any symptoms. But at other times, your symptoms may flare up.

It’s thought than between 1 and 3 in every 100 people in the UK have psoriasis. It can start at any age. But it’s more likely to begin when you’re between 20 and 30 or between 50 and 60. Psoriasis affects men and women equally. It isn’t contagious so you can’t catch it or pass it on to anyone else.

Psoriasis causes

It’s not clear exactly why some people develop psoriasis. But genetics is thought to be a major factor. You’re more likely to get it if other people in your family have the condition.

Psoriasis seems to affect how your immune system responds to different factors. Certain factors can trigger the onset of psoriasis. These triggers can also cause a flare-up if you already have the condition.

Trigger factors include:

• throat infections
• an injury to your skin – including scratches, burns or getting a tattoo or piercing
• certain medicines including lithium, some antimalarial drugs, some drugs for high blood pressure , and certain antibiotics
• sunlight – this usually helps with psoriasis but for some people, sunlight can make their psoriasis worse
• hormonal changes such as those occurring in puberty, after childbirth and during the menopause
• stress
• smoking
• drinking too much alcohol
• being obese

Symptoms of psoriasis

• Psoriasis causes inflamed patches or areas of skin. It can also affect other parts of your body. Your fingernails and toenails may have pitting (tiny holes). They may also become thickened, discoloured or loosened from the nail bed.
• Your joints may be painful, swollen and stiff. This is called psoriatic arthritis. It tends to affect the joints in your hands, feet, knees, and ankles.

There are several different types of psoriasis. Your symptoms will depend on the exact type of psoriasis you have.

Plaque psoriasis

This is the most common type of psoriasis. It’s also called psoriasis vulgaris. You have thickened, red patches of skin. These may be covered with silver-white scales. Some people have lots of plaques, and others have only a few. The plaques can appear anywhere on your body. But they commonly appear on your back, tummy, scalp, knees and elbows. They can also affect your face. They may:

• look pink or red on pale skin, and grey on darker skin
• range in size from 1 centimetre to several centimetres across
• itch and sometimes bleed
• develop a crack if they’re on your hands or feet or over a joint such as your elbow or knee
• sometimes have a pale ring around the plaque
• be very thick on your scalp and look like dandruff
• cause some hair loss if you have scalp psoriasis

Guttate psoriasis

You may have small, scaly, inflamed spots on your body, arms, and legs. These tend to appear over the course of a week. Guttate psoriasis tends to affect children, teenagers and young adults, often after a throat infection. It usually disappears after 3 to 4 months.

Pustular psoriasis

You may have small, pus-filled spots (pustules) on your skin. These may be only on the palms of your hands, the tips of your fingers or toes, or the soles of your feet.

Generalised pustular psoriasis

More rarely, pustular psoriasis can cause pustules to appear over your whole body. This is a severe condition called generalised pustular psoriasis. It usually affects people who already have plaque psoriasis. This is an emergency because it can be life-threatening and needs immediate hospital treatment.

Flexural psoriasis (inverse psoriasis)

This causes patches of smooth, red, shiny skin in areas where your skin folds. This may include your armpits, groin, and genital area.

Erythrodermic psoriasis

This is a rare form of psoriasis in which your skin becomes red and inflamed all over. It can be painful and very itchy. It usually affects people who already have psoriasis. It can come on gradually or suddenly. Erythrodermic psoriasis can be life-threatening, so it’s important to get immediate medical attention.

If you have any of these psoriasis symptoms, contact your GP. If you have erythrodermic psoriasis or generalised pustular psoriasis, you may feel very unwell with a high temperature and fast heart rate. Seek urgent medical attention if you have symptoms of these types of psoriasis.

Self-help for psoriasis

Certain things may make your psoriasis flare up. Your symptoms may improve if you:

• manage your stress levels
• don’t drink alcohol to excess
• stop smoking if you smoke
• lose excess weight if you need to

Sunlight may make psoriasis better, so try to spend plenty of time outdoors. Don’t overdo it though – too much sun can trigger a flare-up in some people. It can also cause sunburn and increase your risk of developing skin cancer , so it’s important to stay safe in the sun .

You should be careful exposing your skin to the sun if you’re using certain psoriasis medicines – for example, acitretin. You may sunburn more easily while taking these medicines.

Psoriasis treatment

There’s no cure for psoriasis. But lots of treatments may help to control your symptoms. You may need to try different ones to find what works best for you. Your GP may be able to prescribe some treatments, but others are only available through referral to a specialist. Which treatments your doctor recommends will depend on:

• type of psoriasis you have
• where it is on your body
• how severe it is

Topical treatments

Topical treatments are products that you apply directly to your skin – creams, lotions and ointments. Your GP may prescribe the following topical treatments for psoriasis.

• Emollients. These moisten, soften and soothe your skin. You should apply them regularly and generously, even when your skin appears to be clear. Emollients can sometimes be the only treatment you need. They may also help other psoriasis treatments to work better.
• Corticosteroid creams. These help to reduce inflammation. You should only use steroid creams for a short time, particularly on your face or genitals and especially if you’re using a stronger steroid. You should stop using them once your skin is clear or nearly clear.
• Vitamin D ointments and lotions. You’ll usually be prescribed these alongside corticosteroid creams. You can also use these preparations on their own, and for longer periods of time than corticosteroid creams.
• Salicylic acid-containing products. These can be useful on the scalp, where they help to reduce scaling.
• Coal tar ointments and shampoos. These may be an option for psoriasis on your scalp, body or limbs that hasn’t cleared up with other treatments. Older products can smell and be messy – they may stain skin and clothing. Newer, branded products are less likely to have these problems.
• Dithranol creams. Your doctor might prescribe this if other treatments haven’t worked. It’s usually only used on tougher skin, such as the skin on your elbows and knees. You leave the cream on for a short time before washing it off. The treatment can stain, so take care when using it.
• Calcineurin inhibitors such as tacrolimus and pimecrolimus. These are often used in areas that are difficult to treat such as your face or skin folds. A specialist will usually need to prescribe these.

If topical treatments don’t completely control your symptoms or your psoriasis covers a lot of your body, your GP may refer you to a dermatologist. A dermatologist is a specialist in skin conditions and will be able to discuss additional treatment options.

Light therapy

Your doctor may offer you ultraviolet (UV) light therapy for mild-to-moderate psoriasis when creams and ointments aren’t enough. This is also called phototherapy. You have light therapy at hospital. You stand in a special unit where you’re exposed to ultraviolet fluorescent lights. There are two types of light therapy.

• Ultraviolet B (UVB) light therapy. This uses a small part of the UVB light naturally found in sunlight. You might have this to treat plaque psoriasis or guttate psoriasis.
• Ultraviolet A (UVA) light therapy with psoralen (PUVA). This involves taking a medicine called psoralen before having light therapy. Psoralen makes your skin more sensitive to UVA light.

Light therapy usually involves two or three sessions a week for between 6 and 12 weeks.

Phototherapy is very different from using sunbeds, which don’t improve psoriasis. With phototherapy, the dose and strength of the ultraviolet light are carefully controlled.

Commercial sunbeds don’t filter the type and dose of ultraviolet light you receive. Most commercial sunbeds use a lot of UVA light, which doesn’t help psoriasis on its own.

Tablets and capsules

Several medicines for psoriasis are available in tablets that you swallow. These include methotrexate, ciclosporin, acitretin and apremilast. These medicines work by reducing the activity of your immune system or slowing down the production of skin cells. Your doctor may prescribe them if you have severe psoriasis and other treatments aren’t helping. They can be very effective. But they can cause severe side-effects so your doctor will want you to have regular check-ups.

Some of these medicines can be harmful during pregnancy. You may be asked to take precautions not to get pregnant (or not to get your partner pregnant). Ask your doctor for more details if you’re considering trying for a baby.

Injections

If your psoriasis is severe and other treatments haven’t helped or aren’t suitable for you, your doctor may suggest a biological medicine. Biological medicines are given as injections under your skin or infusions into your vein. Biological medicines block chemicals in your body that cause inflammation. Examples include etanercept, infliximab, ustekinumab and ixekizumab.