Psoriasis is a skin condition that causes red, flaky patches of skin on the body.
Medically reviewed by Dr Roger Henderson and Based on a text by Dr Flemming Andersen
Psoriasis is a chronic autoimmune skin disease that causes red, flaky patches of skin on the body and 8 million people in the UK are believed to suffer with the condition. With symptoms including red scaly skin and itching, it can have a significant impact on your confidence and your self-esteem, but there are treatments available to ease the discomfort.
We look at the causes, symptoms and treatment options for psoriasis:
What is psoriasis?
Psoriasis is a chronic, recurring skin disease. Its scope can vary considerably; from mild outbreaks, where the person may not even be aware they have psoriasis, to severe cases, which can be socially disabling and, in rare instances, life-threatening.
In principle, people of all ages can get psoriasis, but the early-onset form of the disease is mostly seen in 16 to 22-year-olds and the late-onset form strikes those between the ages of 50 and 60.
Psoriasis is derived from the Greek word ‘psora’, which means itch and around 2 per cent of the population have it.
Psoriasis is derived from the Greek word ‘psora’, which means itch. Around 2 per cent of the population have psoriasis to a greater or lesser degree. Psoriasis is not contagious.
What causes psoriasis?
Psoriasis is a condition which runs in families, but the exact way in which the disease moves from generation to generation has not yet been established.
Although the tendency to contract psoriasis is stored in a person’s genes, it is by no means certain that it will ever develop. However, exposure to certain stimuli (such as a streptococcal infection in the throat, alcohol, certain medicines and local irritation) or damage to the skin, may cause an outbreak of psoriasis in persons who have this genetic predisposition. Stress can also trigger psoriasis.
There are two main types of psoriasis:
- Psoriasis vulgaris: plaque psoriasis
- Psoriasis pustulosa: pustular psoriasis
By far the most common type is plaque psoriasis which affects up to 90 per cent of people with this condition.
The different types of psoriasis can be divided into subgroups according to severity, duration, location on the body and appearance of the lesions.
Around 6 per cent of the people who have psoriasis also get psoriatic arthritis in the joints. Psoriatic arthritis primarily occurs in fingers and toes, but is also quite common in the spine.
Psoriasis vulgaris symptoms
Psoriasis vulgaris is the most common form. The first signs of an outbreak are red spots or patches that grow bigger and become scaly. The upper scales then fall off in large quantities, while the lower layers of scales are firmly fixed and when the scales are scraped off, a number of small, bleeding points can be seen underneath.
• Psoriasis of the nail
Psoriasis of the nail often manifests itself as small indentures in the nails. The outbreak can be so severe that the nail thickens and crumbles away
• Flexural psoriasis
Flexural psoriasis is also a type of chronic plaque psoriasis that occurs in skin folds (flexures). Red, itchy plaques appear in the armpits, under the breasts, on the stomach, in the groin or on the buttocks. The plaques are often infected by the yeast-like fungus candida albicans.
• Guttate psoriasis
Guttate psoriasis is a special variant which primarily occurs acutely in children and young people due to a streptococcal infection of the throat. Drop-like, scaly patches appear on the entire body. In many cases, the condition disappears by itself after a few weeks or months.
• Psoriasis of the scalp
Psoriasis of the scalp can be difficult to distinguish from a severe case of cradle cap, and sometimes the two occur simultaneously. An outbreak of psoriasis can lead to lesions on the face, ears or hairline.
Pustular psoriasis symptoms
Pustular psoriasis is the second most common type of psoriasis where the inflammation is so severe that, in addition to the usual lesions, blisters or pustules containing fluid appear on the skin. It can affect the whole body but more usually the palms of the hands and the soles of the feet. The pustules are not infectious and the severity of the condition varies.
Psoriasis risk factors
People who have family members with psoriasis (around 30 per cent of people with psoriasis have a family member with it) are at greater risk, especially if they are exposed to stress, alcohol abuse, infections, medical treatment, or stressful events such as divorce, bereavement or moving house.
A psoriasis diagnosis is usually made after a careful examination of the skin. If there is any doubt about the diagnosis, the doctor will take a biopsy – a small portion of the skin which will be sent to a specialist for examination under a microscope.
It is important to accept that psoriasis is a chronic, long-lasting condition. The disease is usually characterised by alternate good periods and periods with outbreaks. If you discover that certain things make your psoriasis worse, try to avoid them. It should be noted that all degrees of psoriasis can be treated effectively. The treatment is not a cure, but it will ensure a better quality of life.
If you discover that certain things make your psoriasis worse, try to avoid them.
The treatment, which should be carried out in close collaboration between the patient and the GP or the dermatologist, consists of various treatments used locally on the skin and taken by mouth, depending on the patient’s age, state of health and on the nature of the psoriasis, and usually include the following:
✔️ Lifestyle factors
Lifestyle factors such as smoking, alcohol, stress and being overweight should all be addressed early on as these have a worsening effect on psoriasis.
Moisturisers are an important factor in treatment for psoriasis and may be all that is needed for mild psoriasis. They reduce dryness, cracking and scaling of the skin and also reduce the need for active treatment.
✔️ Local treatments
Specific local treatments include creams and ointments containing coal tar, dithranol, tazarotene or vitamin D-related compounds, eg calcipotriol, calcitriol or tacalcitol.
✔️ Corticosteroid-containing ointments
Occasionally, corticosteroid-containing ointments are used for a short time.
✔️ Combining treatments
Combining a corticosteroid with another topical treatment, either as separate products used at different times of day, or as a combination product, eg Dovobet (calcipotriol and betamethasone) or Alphosyl HC (coal tar and hydrocortisone), may be beneficial for chronic psoriasis vulgaris.
✔️ Scalp lotions
Special lotions are available for scalp treatment. These often contain salicylic acid, coal tar, sulphur or corticosteroids. Vitamin D scalp applications are also available.
✔️ Phototherapy or psoralen ultraviolet
Phototherapy (ultraviolet B, UVB) or psoralen ultraviolet A, PUVA are both used in specialist dermatology centres for widespread psoriasis. Many patients find that natural sunlight also helps.
Oral treatment with immunosuppressants such as ciclosporin or methotrexate, or the vitamin A derivative acitretin may be used for patients with severe, widespread or unresponsive psoriasis.
Injections of the immunosuppressants etanercept, adalimumab, ustekinumab or infliximab may be used for people with severe plaque psoriasis that has failed to respond to ciclosporin, methotrexate or photochemotherapy, or for people who can’t take or tolerate these treatments. These are only used on the advice of a specialist.