My doctor is too busy with people who have problems more serious than mine to keep bothering her about different treatments.

It might sometimes seem this way, but it is important that you feel able to see your GP whenever you need to discuss the treatments you are using and whether they are working or not. Your GP is there to provide care to all the patients on her books and she will not think that you are any less important than the other people she sees.

If, however, you feel that you are not getting the information you need about the treatments from your GP, you might like to ask whether there is anyone else who can help there may be a nurse available who has more time to discuss things with you. It may also be worth considering making contact with the Psoriatic Arthropathy Alliance or the Psoriasis Association. Both are organisations with access to information about treatments as well as being support groups of people with psoriasis who may be experiencing the same sort of thing as you.

Which is the best treatment to put on my scalp?

The treatment that you use on your scalp will depend very much on the extent to which it is affected and what you want to achieve.

Coconut oil: This is good if your scalp is dry but not necessarily covered with active psoriasis. It is solid at room temperature but melts on contact with the skin and is therefore quite greasy; it has a very light but not unpleasant smell. Use as much as you need to make your scalp feel comfortable.

Coal tar solution (Cocois): If the psoriasis on your scalp is thick and active, this is the best treatment to use, as it moistens the plaques and encourages them to lift off. Because it has tar in it, though, it tends to be a bit messy and has a distinctive smell. The amount you use will depend on how thick your psoriasis is, but apply enough to turn the scale from white to the colour of the ointment.

Steroid (e.g. Betnovate) scalp application: This is useful for short-term treatment if your scalp is inflamed but the plaques are not particularly thick. (Beware, though: the scalp application is an alcohol- based solution and can sting when applied.) It is relatively clean and odour free.

Vitamin D scalp application: This is useful when the plaques are thin but active. It is clean and odour free. One or two drops are enough to cover an area of your head about the size of a postage stamp.

It is very difficult to apply my scalp treatment Have you any advice?

With scalp treatment, the method of application is almost as important as which treatment you use. Applying the treatment involves parting the hair in sections and rubbing the treatment along the exposed area. It is best to do this in a sequential fashion, starting at the front of the scalp and working your way round. If the scale/plaques are very thick, once they have been moisturised with the treatment (especially Cocois) they can be gently lifted up using a comb.

It is easier to get someone else to do this for you, as it is difficult to see the top of your head and (a) rub the treatment in where it is needed and (b) lift the scale where appropriate. When doing this some hair may come out, but it will grow back so don’t be too perturbed! The best time to do a scalp treatment is before going to bed, because the treatment (especially Cocois and coconut oil) will make your hair look greasy and can smell.

Try wearing a cotton night cap, a shower cap or something similar and cover your pillows with old pillowcases to protect them. (You can buy pillowcase protectors from bed-linen shops/departments, which give useful extra protection to your pillows.) Wash your hair the next morning with an anti-psoriasis shampoo (i.e. tar-based). An advantage of the coconut-based treatments is that they are wonderful conditioners for your hair!

UV light treatments, and sunlight (Dead Sea) Why is natural sunlight such a good healer?

Natural sunlight is a good healer for many people with psoriasis, but there are some who do not respond and some who are made worse. Sunlight consists of several different types of light across a spectrum ranging from infra-red, through visible light, to ultraviolet (UV). It is the ultra-violet part that can help in treating psoriasis.

The skin cells contain specialised molecules (called chromophores) that are capable of absorbing the energy from UV light and then releasing it to power chemical reactions that affect the function of the cells. In psoriasis, this can result in the cells not multiplying so rapidly and behaving more like normal skin. A lot has been said about the Dead Sea and its benefits, and I understand that some countries such as Germany will help towards the cost of treatment there.

Would it not make more sense for the NHS to pay for patients to go there (Dead Sea) rather than pay for expensive drug treatment here?

This is an attractive but rather over-simplified view. The combination of the concentrated salt solution that is the Dead Sea and strong sunshine does seem to be of benefit but the precise mechanism has not been fully evaluated. The seawater also contains some tars that may also be of benefit. Holidays in sunny places can be relaxing and if other people with psoriasis are at the same resort you would be much less afraid to take your clothes off and expose your skin, thus getting more benefit from the sun.

As the Dead Sea is below sea level, the atmosphere is relatively thicker and absorbs some of the UVB light that causes burning. This means that you can get a higher concentration of the helpful UVA light without burning, but this could lead to higher risks from skin cancer. Most of the reviews of Dead Sea treatment mention treatment times of under three hours. It is thought that the complex salt solution adds to the efficacy of natural sunlight and may in itself have some effect on skin cell turnover.

Even the dermatologists from the Ben Gurion University in Israel stress that treatment guidelines and standards have to be set in order to assess the cost effectiveness of Dead Sea therapy compared with other treatments. The NHS has to be very careful about spending money in this way, and many other patients might demand holidays because they feel better afterwards.

Why is it thought that the immune system plays a part in causing psoriasis?

There are several reasons why the immune system is felt to be important in causing psoriasis. Some immuno-suppressive drugs (which damp down some parts of the body s immune reaction) work well in treating psoriasis. It is also a life-long disease, and this is taken as a sign that there is some memory in the immune system that produces the typical rash of psoriasis in response to certain triggers. This memory is part of the way our immune system works in recognising foreign bacteria and fighting them, and explains why immunisation prevents us developing certain diseases.

The way the disease can also clear up without treatment and then flare up again is also typical of a long-term immune response. Finally, some of the genes identified are known to be linked to the way our immune system works.

Are there any non-Chinese herbal remedies?

Yes, there is a strong tradition of Western herbal medicine, with its origins going back into folklore. Unfortunately, there seems to be even less published work in this area, so very little evidence exists on which someone with a conventional approach can base advice. Herbalists do spend time taking a good medical history and tend to use creams that can be soothing and act as a good emollient, if nothing else.

Many of our modern remedies have been produced after the study of traditional plant-based remedies, but an active ingredient needs to be identified and thoroughly tested before it can be licensed as a drug. This method may well ignore the beneficial effects of groups of extracts that, on their own, may be ineffective but which work well together.