One important element of its marketing is a recently completed study involving 300 patients, who were given 0.1 per cent or 0.05 per cent tazarotene gel once a day, or the steroid cream fluocinonide twice a day.

Overall improvement was similar among both treatments, but fewer of the tazarotene group suffered a relapse 12 weeks after the therapy had finished.

Although, as a gel, it’s easy to apply, it also seems to be less well tolerated than some of its competitors. More in the tazarotene group had to drop out because of side effects, which included irritation, burning and erythema (skin reddening) (J Am Acad Dermatol 1998; 38: 705-11).

To this can be added the adverse reactions noted in earlier trials, such as pruritus (itching), experienced by up to a quarter of all patients, and a worsening of the condition, which was reported by up to 10 per cent of all patients.

Not surprisingly, reaction is associated with higher concentrations of the gel. The higher concentration gel of 0.1 per cent can cause up to 5 per cent more cases of severe skin irritation than the lower concentration, especially during the first four weeks of use, the manufacturer warns.

Pregnant women and breastfeeding mothers should not use the gel, nor should any woman thinking of becoming pregnant. Its safety among patients under the age of 18 has not been proven.

Calcipotriol (Dovonex). Early studies indicate that it is at least as effective as the steroid betamethasone, if not more so, for plaque psoriasis (K Kragballe et al, The Lancet, 26 January 1991), and is superior to short term dithranol. It should never be used for the face as it produces soreness. Calcipotriol should never be used by fair skinned people who burn easily in the sun; patients who have recently had courses of etretinate, which increases skin sensitivity; and patients who have been treated with strong corticosteroids long term. It should be used only six weeks at a time. Patients need to be careful about exposure to the sun with it. Maximum recommended amount is 100g a week.

Cyclosporin. This is increasingly used for refractory psoriasis. It is a powerful immunosuppressant, extensively used in organ transplants. A US study (Charles Ellis et al, University of Michigan Medical Centre, NEJM, 31 January 1991) of 85 plague psoriasis sufferers found that with a dosage of 5 mg per day, 65 per cent had almost complete clearance. But at what cost? With long term use cyclosporin causes hypertension and nephrotoxicity (kidney damage).

French doctors writing in the New England Journal of Medicine (13 June 1991) reported that cyclosporine therapy results in frequent neurological complictions, including coma and convulsions. Because of its toxicity, its use is restricted to hospital dermatologists.

Topical steroids such as Dermovate have adverse effects from excessive use such as harm to the adrenal glands, and serious flare ups after withdrawal. Most UK dermatologists reserve them for special circumstances (A J G McDonagh, Rupert Hallamshire Hospital, Sheffield, The Lancet, 31 August 1991). Dermovate, the steroid of steroids, should only be used for a short course of a month or more. Glaxo, its manufacturer, warns against using the drug on the face for more than five days, since longer use might cause “atrophic changes”, that is, wasting of the tissues. Avoid usage around the eyes, because it can cause glaucoma. Glaxo goes on to warn that topical steroids in general can cause rebound relapses, create tolerance, spark off generalized “pustular psoriasis” and cause a local or systemic toxicity “due to impaired barrier functions of the skin”. In other words, the drug itself may create a vicious cycle which causes your psoriasis to worsen.

Fish oil . Lower incidence of psoriasis among Greenland Eskimos, attributed to the mainly fish diet, high in omega 3 fatty acids, sparked clinical trials which have shown an improvement with the addition of fish oil to the diet. (Geraldine McCarthy, Medical College of Wisconsin, The Lancet, 28 September 1991).

Dithranol. (Cignolin in Europe, and Anthralin in the US) remains the most effective topical treatment, and has been the mainstay of topical treatments for 65 years. It should not touch normal skin as it causes irritation. Strengths should be increased from 0.1 up to 1 per cent if tolerated. Initially the cream should be left on for half an hour, but this can be increased to one to two hours. It cannot be used on the scalp and face. (GP Clinton Hale, MIMS Magazine, 15 August 1991).

However, it causes a brownish purple staining of the skin; bandages are required and clothes and bedding become ruined as the stains cannot be washed out. It can burn off the top layer of skin if the strength is not carefully controlled. A new Dithranol stick makes application easier.

Coal tar shampoo for mild scalp conditions. Coal tar (Alphosyl) lotion or cream in moderate scalp conditions.

White soft paraffin for five or fewer lesions. Emollients added to the bath can soften plaques.

Ultraviolet light B can be given twice weekly for two months. It claims to clear generalized plaque in 85 per cent of patients. Main disadvantages are that the patient has to attend hospital, and the risks include phototoxic reactions, increased photoageing and an increased incidence of skin malignancies. A UVA unit will not help; that is for tanning only.

PUVA (psoralen + UVA). As above, but patient is given psoralen tablets (a photosensitizing drug) two hours before the body is irradiated and has to wear protective glasses for 24 hours afterwards. However, there is an increased risk of genital tumours (Stern et al, NEJM, 19 April 1990).

Methotrexate (Maxtrex) is a maintenance treatment for extensive psoriasis when resistant to topical treatment. Not for pregnant women or people with liver disease, significant renal impairment, bone marrow suppression or excessive alcohol consumption (some say no drinking at all should be allowable). Main side effect is liver fibrosis. Other side effects include nausea, indigestion, loss of appetite, abdominal pain, fatigue, ulcers, haemorrhaging and hair loss. Used since 1955 to treat psoriasis, it is better known for its use to treat cancer, including leukaemia and Hodgkin’s disease, and is also sometimes used to reduce the risk of kidney rejection after transplant.

Synthetic retinoids are related to vitamin A and are useful in extensive plaque psoriasis. However, side effects include raised cholesterol, hepatitis, hair loss and skin fragility. Patients can also experience dryness and irritation of the eyelids and lips, and skin thinning .

Benoxaprofen has been withdrawn because of serious side effects, but the British medical authorities have approved a limited number of trials with psoriasis.

The three doctors from Harvard and Dartmouth Medical Schools say that Sandoz distributed a report entitled “Consensus Report: Cyclosporine-A for Psoriasis”. This was produced at a conference in Spain sponsored by the drug company whose participants included employees of and one dermatologist paid by Sandoz.

This was sent to selected American dermatologists, say the doctors, and Sandoz was so keen on getting them to read it that it offered $l00 for completing a “brief quiz” and engaged in follow up telephone calls to encourage the doctors to complete it.

Speaking for Sandoz, Dr David Winter wrote in to the Journal of the American Medical Association to say that the questionnaire was a “market research tool” designed to determine whether there was sufficient interest in cyclosporine to embark on the testing required to get drug approval. The time spent filling out the form seemed to warrant the $l00 fee, he said. “To consider any of these activities as promotional does seem to be a manipulation of information.”

Echoing the AMA Drug Evaluations and the US Pharmacopeia Drug Index, which says there is not enough data to prove the drug’s safety for psoriasis, Sandoz reports in the Physician’s Desk Reference that the drug causes liver and kidney toxicity, that lymphomas have formed and that one in l000 patients undergoes anaphylactic shock. There’s also substantial risk of hypertension, convulsions, and even heart attacks.

Prickly heat (and itchy skin, thrush etc.) may be a symptom of Candida overgrowth. Try an anti-Candida diet, so cut out sugars, simple carbohydrates, and remove fruit – and especially bananas – for a while. . .

With hayfever season upon us (certainly for us in the West), the Bowen technique may help relieve symptoms, says one reader, who is presumably a Bowen practitioner. . .

Threadworms can be treated by eating only halal or kosher meat as any microbes are drained out with the blood.

Alternatively, try Elnas Nature Collection of creams and oils, available from Dulwich Health (020 8670 5883), while another reader suggests that our questioner sees a health kinesiologist as the eczema may be linked to some allergy.

Nutritionally, try vitamin B9 and B12 and C, while a lack of vitamin A can aggravate psoriasis. One woman found her son started developing eczema after she stopped breastfeeding, suggesting a food allergy. Remove all refined foods, and especially white flour, white sugar, white rice and pasta, from the diet, and don’t have any citrus, including orange juice, no artificial additives, and no sweets, chocolate, pop, squash, cakes, crisps etc.

Another reader wonders if the cause may have been antibiotics, which may have caused Candida. Oxygen therapy, combined with an anti-Candida diet, did the trick.

Stellaria cream is another option, or try aloe propolis cream.

* In a recent study, one third of 773 individuals involved in a road accident as a driver, bicycle rider or pedestrian experienced some level of anxiety, depression, fear of travel or post traumatic stress disorder (PTSD) 3 to 12 months later and, in most cases, persisted. After one year, about half the group had phobic travel anxiety, nearly 60 per cent had general anxiety, and half were diagnosed with PTSD (Am J Psychiatry, 2001; 158: 1231-8).

* New research in nearly 1300 men suggests that, during a severe asthma attack, men are less likely than women to notice the symptoms of the attack. The reason for this is unclear, but it may be that men perceive less discomfort because of greater lung size and muscle strength, or because they generally develop asthma at an earlier age than women. Men also tend to only seek medical attention when symptoms are too severe to ignore, the researchers noted (Ann Emerg Med, 2001; 38: 123-8).

* What’s lurking in that paddling pool? Physicians in Canada have found the first outbreak of a new type of Pseudomonas infection called ‘hot foot syndrome’. This discovery was made when 40 children, aged 2 to 15, developed intense pain in the soles of their feet within 40 hours of using the same wading pool. A hot, red swelling began after a few hours, along with pain so severe that the children were unable to stand up. Three children were given oral cephalexin (an antibiotic) while the others were treated with cold compresses, analgesics and foot elevation. In all cases, the condition resolved within 14 days, although it recurred in three children after they revisited the same pool (N Engl J Med, 2001; 345: 335-8).

Possibly to their own surprise, the approach appears to have helped make the topical steroids for psoriasis more effective. But of the 30 patients in the treatment group, 18 did not complete the course.

It’s not clear if the problem was down to a drug reaction, but now the doctors have stumbled on a fact long since recognised by the alternative camp,which is that perhaps a more benign approach could be tried.

Results showed that the risk of psoriasis was higher in smokers than in those who’ve never smoked and that this link was stronger in women than in men. Smoking more than 15 cigarettes a day was strongly associated with pustular lesions.

The multicentre, case controlled study involved outpatients in ten general and ten teaching hospitals in southern and northern Italy. Patients with a first diagnosis of psoriasis and a history of symptoms of less than two years were matched with controls who had a history of skin problems other than psoriasis (Arch Dermatol, 1999; 135: 1479-84).

Recent research adds weight to a study in 1985, which first linked smoking to the skin condition.

Hywel Williams, a research fellow at St Thomas’s Hospital in London, estimates that smoking may have triggered up to half the cases of palmoplantar pustular psoriasis characterized by thickened plaques on the palms and soles of the feet, which can become cracked and painful.

He said that smoking and drinking should now be added to the growing list of likely causes, alongside trauma, drugs and emotional stress.

“Any progress in identifying modifiable risk factors for this common and socially disabling disease is to be welcomed and it is more useful than reports of temporary remission with expensive and potentially toxic drugs,” he says (BMJ, 12 February 1994).

No research for smear tests

While the British press has been highlighting the blunders of health authorities in failing to recall women for follow up smear tests, they have missed a more fundamental problem.

Britain’s chief medical officer Dr Ken Calman has admitted the cervical smear programme has been implemented ad hoc since the 1960s with no research evidence, leading to variations at the local level. He said the screening programme for hearing loss in children also needed reviewing.

In the UK, over 25,000 cases have so far been reported of women who have failed to receive a follow up request, usually because of an administrative error. The latest case was in South London.