This information was published by Bupa's health information team and is based on reputable sources of medical evidence. It has been peer reviewed by Bupa doctors. The content is intended for general information only and does not replace the need for personal advice from a qualified health professional.
Psoriasis is a common skin condition that causes raised patches of inflamed skin. It varies in severity from person to person and can come and go over time. You can’t catch psoriasis or pass it on to other people.
Your skin is made up of several layers, the top one of which constantly sheds old cells and replaces them with new ones from underneath. This happens in a cycle that usually takes about 28 days. If you have psoriasis, the rate at which your skin is replaced in the affected area increases and the cycle can be as short as two to six days. New skin cells move to the surface before they have properly matured and build up on your skin in thick patches called plaques. There is also a build-up of a type of blood cell (called T-cells) under your skin, which causes inflammation.
Psoriasis affects about two in 100 people. It can begin at any age, but commonly develops either in early adult life between the ages of 15 and 30 or later between 50 and 60. It affects similar numbers of men and women.
Psoriasis is a life-long condition and it’s unlikely that you will ever be completely free of it. However, it tends to fluctuate in severity over time, often for no apparent reason. This means that you may have flare-ups when the symptoms are more severe, but at other times the condition may hardly be noticeable.
Psoriasis isn't contagious, so you can't catch it from other people and it doesn't spread from one part of your body to another.
There are a number of different types of psoriasis.
Plaque psoriasis is the most common type of psoriasis, where you get pinkish-red, scaly plaques (raised patches), especially on your knees and elbows.Insert Photo: Plaque psoriasis (All original photos can be downloaded from our file sharing website. Contact the Health Information Team for log in details).
Flexural psoriasis is also known as inverse psoriasis. It affects areas where your skin folds, such as your armpits and groin area. Your skin tends to be thinner and more sensitive in these areas. Flexural psoriasis causes patches of bright red, shiny skin – these may be slightly itchy or uncomfortable. You may have flexural psoriasis at the same time as having plaques elsewhere on your body.
This is a rare, severe form of the condition in which small pus-filled spots (pustules) develop on your skin. If this happens all over your body, it's called generalised pustular psoriasis. This can be a life-threatening condition and you’re likely to need to be treated in hospital.
Erythrodermic psoriasis is another rare and severe form of the condition in which your skin becomes red and inflamed all over – it looks like sunburn. The inflammation can result in serious complications and usually needs to be treated in hospital. Erythrodermic psoriasis usually only develops in people who already have another type of psoriasis.
In this form of psoriasis, small, scaly, inflamed spots of skin suddenly appear all over your body – their appearance is sometimes described as looking like rain droplets. It tends to affect children and young adults, often after a throat infection.
Symptoms of psoriasis
Psoriasis occurs in different forms, but you will usually have thickened, red patches of skin, which may have silver/white scales. The patches can vary in size and are clearly defined from the surrounding skin. Your skin may feel itchy, painful or sore. If you have mild symptoms, you may not be aware that you have psoriasis.
Some types of psoriasis can affect your scalp and cause redness and flaking. It can also affect your fingernails, which can become pitted, thickened or loosened from the nail bed.
If you have any of these symptoms, see a doctor.
The exact reasons why you may develop psoriasis aren’t fully understood at present. It appears that your genes are the most important factor in causing the condition because you're more likely to get psoriasis if other people in your family have it. However, this doesn’t mean you will definitely get the condition.
Environmental factors also play an important role in triggering psoriasis. These include a bacterial throat infection, the effects of certain medicines or stress. For many people, there is no obvious cause.
The genetic and environmental triggers lead to immune cells in your skin setting off inflammation. This causes your skin to start producing new cells faster than usual, leading to psoriatic plaques. What makes your immune system act like this isn't clear.
Your doctor will ask about your symptoms and examine you. He or she will probably be able to diagnose psoriasis from your symptoms and by looking at your skin and nails. Your doctor may refer you to a dermatologist (a doctor who specialises in identifying and treating skin conditions) if a definite diagnosis can’t be made or if your psoriasis is:
- extensive or severe
- affecting your education or work
- not responding to treatment
If you have generalised pustular psoriasis or erythrodermic psoriasis, you may need to go to hospital for urgent treatment.
Although there is no cure for psoriasis, there are a number of treatments that can help relieve your symptoms. Treatments vary in how effective they are for different people and you may need to try several before you find one that works for you.
Your doctor may advise you to use emollients – creams or lotions that moisten, soften and soothe your skin. Having a warm bath may help to soften your psoriasis – your doctor may suggest adding bath oil.
These are treatments that you apply to your skin. Your doctor may prescribe you a medicated cream or ointment – the type and strength will depend on your psoriasis, but common treatments include the following.
- Coal tar preparations can reduce inflammation and scaling, and are often used to treat psoriasis affecting your scalp. However, they can be smelly and messy.
- Creams that contain dithranol can be very effective, but they are messy and can irritate healthy skin, so they aren’t often prescribed.
- Steroid preparations are often used for localised psoriasis (for example, on your elbows or knees). You may be able to use stronger steroids on your palms and soles, or your scalp. Generally, steroid creams are only used short-term.
- Vitamin D derivatives (such as calcipotriol or tacalcitol) can be easier to use than some of the other products, but may irritate your skin.
- Vitamin A derivatives (retinoids) can be useful, but they are prone to causing skin irritation.
Always ask your doctor for advice and read the patient information leaflet that comes with your medicine.
If topical treatments don't control your symptoms, or if your psoriasis is extensive, you may be prescribed medicines that you take as tablets, such as:
These medicines work by suppressing your immune system, or by slowing down the production of skin cells. They can have severe side-effects and need to be prescribed by a doctor.
Women will be warned not to become pregnant while taking these medicines and, in some circumstances, for some time afterwards. With some of the tablets, men will also be advised that they shouldn't get their partner pregnant. This is because these medicines can cause serious damage to an unborn baby.
Biological medicines are newer treatments for psoriasis that can be very effective, but tend to be restricted to people with severe psoriasis, or if other treatments haven’t worked. They are given as an injection into your skin, or through a drip into a vein in your arm. These medicines include:
Your doctor can discuss these treatments with you. You will need to have various pre-treatment tests before you can try these medicines and you will be monitored with blood tests while you're receiving the treatment.
Always ask your doctor for advice and read the patient information leaflet that comes with your medicine.
Availability and use of medicines may vary from country to country.
Depending on the type and extent of your psoriasis, your doctor may recommend that you have ultraviolet (UV) light therapy.
You have the light therapy in a machine that looks similar to a shower cubicle, containing fluorescent tubes.
- Ultraviolet B (UVB) light therapy involves shining artificial UVB light on to your skin. UVB light occurs naturally in sunlight. You will usually have the therapy two to three times a week for up to eight weeks.
- Sometimes UVB light therapy is used in combination with topical treatments such as coal tar preparations. This combination may be effective at helping to control your symptoms by making your skin more sensitive to UVB light.
- Psoralen and UVA light therapy (PUVA) involves combining a medicine (psoralen) that sensitises your skin to sunlight with a controlled dose of UVA light. You may have psoralen as a tablet or applied directly to your skin. You usually have the treatment twice a week for up to 10 weeks.
Availability and use of different treatments may vary from country to country. Ask your doctor for advice on your treatment options.
- Psoriasis – an overview. The British Association of Dermatologists. www.bad.org.uk, published May 2012
- Psoriasis. eMedicine. www.emedicine.medscape.com, published June 2012
- Psoriasis: signs and symptoms. American Academy of Dermatology. www.aad.org, accessed 13 June 2012
- Guttate psoriasis. eMedicine. www.emedicine.medscape.com, published May 2012
- Psoriasis. DermNet NZ. www.dermnetnz.org, published May 2012
- About psoriasis. The Psoriasis Association. www.psoriasis-association.org.uk, accessed 13 June 2012
- Psoriasis. Prodigy. www.prodigy.clarity.co.uk, published May 2010
- Etanercept and efalizumab for the treatment of adults with psoriasis. National Institute for Health and Clinical Excellence (NICE), 2006. www.nice.org.uk
- Infliximab for the treatment of adults with psoriasis. National Institute for Health and Clinical Excellence (NICE), 2008. www.nice.org.uk
- Ustekinumab for the treatment of adults with moderate to severe psoriasis. National Institute for Health and Clinical Excellence (NICE), 2010. www.nice.org.uk
- Ultraviolet light therapy. The Psoriasis Association. www.psoriasis-association.org.uk, accessed 14 June 2012
- Personal communication, Dr M Ardern-Jones, Consultant Dermatologist/Senior Lecturer, Sir Henry Wellcome Laboratories, Southampton General Hospital, June 2012
- Psoriasis – a simple explanation. The Psoriasis and Psoriatic Arthritis Alliance. www.papaa.org, accessed 14 June 2012
- Frequently asked questions. The Psoriasis and Psoriatic Arthritis Alliance. www.papaa.org, accessed 14 June 2012
- Frequently asked questions: psoriasis in spring, summer, fall and winter. The National Psoriasis Foundation. www.psoriasis.org, accessed 14 June 2012
- Ebetrex 10mg/ml solution for injection, pre-filled syringe. electronic Medicines Compendium. www.medicines.org.uk, published March 2012
- Hydrea 500mg hard capsules. electronic Medicines Compendium. www.medicines.org.uk, published June 2012
- Neoral soft gelatine capsules, Neoral oral solution. electronic Medicines Compendium. www.medicines.org.uk, published February 2012
- Neotigason 10mg capsules. electronic Medicines Compendium. www.medicines.org.uk, published July 2011
- Condoms (male and female): your guide. The Family Planning Association. www.fpa.org.uk, published March 2011
- Sunbeds. The British Association of Dermatologists. www.bad.org.uk, accessed 15 June 2012
- Exposure to artificial UV radiation and skin cancer. International Agency for Research on Cancer, 2006, Working Group Report 1. www.iarc.fr
- What is skin camouflage? Skin Camouflage Network. www.skincamouflagenetwork.org.uk, accessed 18 June 2012
- Find out about the skin camouflage team. Changing Faces. www.changingfaces.org.uk, accessed 18 June 2012
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