What Is Psoriasis?

Mild psoriasis (80% of people) is where there are a few patches that may need treatment but are not likely to cause problems and can be easily controlled. Moderate psoriasis (15% of people) is where more skin is involved and the condition is widespread but again can usually be controlled with self management under a GP or nurse supervision. Severe psoriasis (5% of people) is where large areas are covered with psoriasis and the condition becomes difficult to self-manage or no longer responds to treatment. At this stage referral to secondary care at a local hospital out-patient department or in extreme cases an in-patient stay may be felt necessary in order to provide optimum care and monitoring.


Normally a skin cell matures in 21-28 days and during this time it travels to the surface of the skin, where it is lost in a constant invisible shedding of dead cells. In patches of psoriasis the turnover of skin cells is much faster, around 4 – 7 days, and this means that even live cells can reach the surface and accumulate with dead cells. The extent of psoriasis and how it affects an individual varies from person to person. Some may only be mildly affected with a tiny patch hidden away on an elbow which that does not bother them while others may have large visible areas of skin involved that significantly affect daily life and relationships.
This process is the same wherever it occurs on the body.
Psoriasis is not contagious


It affects men, women and children alike. It can appear at any age in varying degrees but usually between the ages of 10 and 30, but can occur at any age from infancy to old age. The severity of the disease can vary enormously – from a minute patch to large patches covering the most body areas. Psoriasis can also run in families and much research is being done into the genetics of this disease. It is known that the disease is multi genetic and therefore children may not necessarily inherit psoriasis.

It is estimated that if 1 parent has psoriasis that there is a 15% chance that a child will develop the condition. If both parents have psoriasis this increases to about 75%. Interestingly, if a child develops psoriasis and neither parent is affected there is a 20% chance that a brother or sister will also get psoriasis. This is because the condition is known to skip generations but somewhere there will be a familial link to a relative via either or both parents.


Unfortunately not at the moment. Much research is being done and in the last decade great strides have been made in understanding what goes wrong in psoriasis, so there is good cause for optimism.

In the meantime there are a number of treatments that are effective in keeping the problem under control. The art of treating psoriasis is finding the best form of treatment for each individual. There is no single solution that is right for everyone.


In the absence of a cure you will always have psoriasis but this does not mean that the signs of it will always be visible. Normally, the rash tends to wax and wane. There will be periods when your skin is good with little or no sign of psoriasis. Equally, there will be times when it flares up. The length of time between clear skin and flare-ups differs for each individual and is unpredictable. It may be weeks, months or even years.


Chronic Plaque discoid psoriasis (psoriasis vulgaris) – Raised, red, scaly patches mainly involving the limbs and the trunk, especially on the elbows, knees, hands, around the navel, over the lower back (sacrum) and on the scalp. The nails may be affected so that they become thickened and raised from their nail beds, The surface of the nail may be marked with small indentations. This is the most common type of psoriasis affecting approximately 9 out of 10 people with psoriasis. Psoriasis usually appears between the ages of 10 and 30, but can occur at any age from infancy to old age.

Guttate psoriasis (Raindrop psoriasis) - So named because it manifests itself over the body in the form of scaly droplet-like shaped patches. Numerous small red scaly patches quickly develop over a wide area of skin, although the palms and the soles are usually not affected. This occurs most frequently in children and teenagers, often after a throat infection due to streptococcal bacteria. Some people will go on in later life to develop chronic plaque psoriasis.

Scalp psoriasis – Raised, red thick scaly plaques on the scalp and around the hairline. It is common and approximately 50% of all people with psoriasis have it on their scalp. The reason it deserves special mention is that it can be particularly difficult to treat and usually requires specifically formulated medicines. It is difficult to treat with creams and ointments because the hair gets in the way.

Flexural psoriasis (sometimes known as inverse psoriasis) - Produces red well defined areas in skin folds (flexures) such as the armpits, between the buttocks and under the breasts. Scaling is minimal or absent. This type of psoriasis can be frequently irritated by rubbing and sweating due to its location in the skin folds and other tender areas. Such areas can also be prone to yeast or fungal infections which might cause confusion.

Napkin psoriasis - Develops in the nappy area of an infant to cause a bright red, weeping rash or more typical psoriasis plaques. A child who has napkin psoriasis as a baby does not seem to have a higher risk of developing other forms of psoriasis in later life.

Palmar plantar pustular psoriasis - Small deep seated pustules form that usually only affect the palms and soles. Pustules are due to the accumulation of white blood cells (polymorphs) and are not infected.

Generalised pustuar psoriasis - Rarely, the pustules are more widespread with fever and a high white blood (cell) count. The development of generalised (pustular) psoriasis requires urgent hospital treatment.

Erythrodermic psoriasis - A rare, serious condition where skin redness known as erythema can affect the whole body. Dilated blood vessels in the skin affect blood circulation to other parts of the body, with problems of fluid balance and rapid heat loss. In severe cases, this may be life-threatening. Erythrodermic psoriasis is very rare. There are approximately 200 - 300 new cases in the UK each year.

Nail psoriasis - In 50% of people with psoriasis there is also major involvement of the nails, with minor involvement being seen in some individuals. The fingernails and toenails are affected equally from one to twenty nails may be affected. Discolouration, pitting and separation from the nail bed are the most common characteristics of activity. Nails can be a good indicator that psoriasis is present and can help the doctor to diagnose if an associated form of arthritis is present.

Psoriatic arthritis (psoriatic arthropathy) – About 10-20% of people with psoriasis may develop an associated arthritis called psoriatic arthropathy, which causes pain and swelling in the joints and connective tissue, accompanied by stiffness, particularly in the mornings. Most commonly affected sites are the hands, feet, lower back, neck and knees, with movement in these areas becoming severely limited. Chronic fatigue is a common complaint linked with this condition. If you are experiencing mild aches and pains and have psoriasis, albeit very mildly, consult your dermatologist for further advice and if necessary a referral on to a rheumatologist for further assessments.


There may not be a cure yet but there is much you can do to help maintain and control your psoriasis. Your general practitioner/dermatologist will be best placed to keep you informed of all new treatments around and to advise you on the best treatment programme for you.

Remember. Your treatment can only be as good as you allow it to be - that means if the treatment takes six weeks, you have to do it as instructed for six weeks and no ducking out! Finding out all you can about psoriasis and having a full working understanding of it can be very helpful in coping with the problem. Look out for any emerging patterns, stress levels and any event that may trigger flare-ups.


A healthy diet is important for well-being and can reduce your risk of many long term illnesses. However, there is no clear link between what you eat and severity of the psoriasis symptoms.

• The British Nutrition Foundation suggests eating at least 300gms of oily fish per week for general health (eg. mackerel, herring, salmon, trout, sardines, pilchards). Fish oil (including salmon) has been shown to benefit psoriasis.
• Aim to eat more green leafy, vegetables, nuts, seeds and wholegrain cereals which also contain important essential fatty acids.
• Cut back on saturated fats and vegetable oils and use more olive oil and rapeseed oil products.
• Eat fresh, home-made foods rather than pre-packaged, convenience food.
• Excessive amounts of alcohol can make psoriasis worse and can also interfere with certain drug medications e.g. methotrexate.

If you think you have psoriasis, go and see your GP. He/she may decide to start treatment themselves or refer you to a dermatologist for advice.

Don't forget if you are also experiencing aches and pains in any of your joints (psoriatic arthritis) or have any other symptoms or if you have a family history of psoriasis, inform the doctor. This will assist with diagnosis and treatment.


Psoriasis Help Organisation
Brtish Association Of Dermatologists
The Psoriasis Association