Causes

The cause of psoriasis is unknown.  There seem to be many contributing factors including faulty immune system, faulty metabolism of Vitamin D, incomplete protein digestion, bowel toxaemia, impaired liver function, excessive consumption of animal fats, nutritional factors and stress.

Symptoms can sometimes be lessened by sunlight and worsened by severe sunburn, winter, stress, minor skin injuries, infections, anti-malarial drugs, lithium and beta-blockers.  Candida albicans overgrowth in the intestines appears to play an important part in some people.

Treatment

Conventional treatment is commonly emollients, corticosteroids with calcipotriene (vitamin A derivative) and coal or pine tar, tazarotene, anthralin.  Very thick patches can be thinned with ointments containing salicylic acid which make the other treatments more effective.  Phototherapy can help; also Dithranol and Psoralen (a light sensitive drug) with UV light.

For psoriatic arthritis: cyclosporine, methotrexate and acitretin. All have serious side-effects.

Herbal Treatment (topical)

• Oatmeal baths. 
• Creams with capsaicin (counter-irritant), chickweed (anti-itch) and/or thuja (anti-mitotic).

Herbal Treatment (internal)

Psoriasis is a classic condition where each patient should be treated individually because the causes are multi-factorial and different from person to person.  Most prescriptions will include herbs to improve liver function, to aid digestion, to remove toxins and to aid elimination through the gut and the kidneys.  They might also include relaxing nervines and adrenal support.

Diet

Dietary advice for psoriasis is often contradictory, for example success has been reported both with a “grapefruit-only” and “non-citrus” diet.  If, however, there is an associated food intolerance (such as gluten or dairy) or an overgrowth of Candida albicans, a specific diet for these conditions is likely to help the psoriasis.
Most dietitians and herbalists agree on the advice in the table below which is well supported by research evidence.

Minerals, vitamins and essential fatty acids

Zinc aids vitamin A metabolism.  Zinc deficiency may cause Vitamin A deficiency which is a common cause of skin disorders.