PSORIASIS
Report #6973; 12/7/96
Several recent reports show that the safest treatment for psoriasis may be a combination of a vitamin D ointment (1) and oral antibiotics (2).
Psoriasis means that you make too much skin. A new skin cell is laid down at its innermost part. Then another cell is laid down underneath that. As each successive new cell is laid down underneath it, the cell over it moves outward, until it is shed as dander or dandruff 28 days later. Psoriasis means that the skin turns over 7 times as fast as normal so cells are shed after only four days, instead of the usual 28. This causes thick plaques to form on top of the skin, particularly at the elbows and knees and the face and scalp develop thick scales, and the nails thicken and grow very fast. So, all treatments for psoriasis are aimed at slowing skin turnover rate to normal. The most common treatment includes cortisone-type ointments, but continued use can cause irreversible thinning. Doctors prescribe light treatments and drugs that sensitize the skin to sunlight (3),
but they can cause skin cancer many years later. For severe psoriasis, doctors use poisons, such as methotrexate, but sulfasalazine is far safer, even though it is not as effective (4). Recently, doctors found that vitamin D slows skin turnover and is not a poison. Vitamin D ointment is applied to the thick psoriatic plaques at bedtime and covered with special plastic wrap. Rapid spread of psoriasis is usually caused by infection, so doctors often prescribe antibiotics, such as cephalosporins, to kill staph and strep two germs that commonly cause psoriasis to worsen.
By Gabe Mirkin, M.D., for CBS Radio News
1) SI Cullen, L Drake, T Kahn, HI Katz, RW Loss, MT Jarratt, T Funicella, C Whitmore, H Luber, A Ison, EL Jones, S Primmer, C Huerter, D Kingsley, H Moss, S Bruce, J Milbauer, I Kantor, J Lederman, J Shavin. Long-term effectiveness and safety of topical calcipotriene for psoriasis. Southern Medical Journal 89: 11 (NOV 1996): 1053-1056. calcipotriene 0.005% ointment is safe and effective.
2) SL Gottlieb, et al. Response of psoriasis to a lymphocyte-selective toxin (DAB389IL-2) suggests a primary immune, but not keratinocyte, pathogenic basis. Nature Medicine 1995; 2: 442-447.
3) Z Evenpaz, R Gumon, V Kipnis, DJ Abels, D Efron. Dead Sea sun versus Dead Sea water in the treatment of psoriasis. Journal of Dermatological Treatment 7: 2 (JUN 1996): 83-86.
4) B Combe, P Goupille, JL Kuntz, J Tebib, F Liote, C Bregeon. Sulfasalazine in psoriatic arthritis: A randomized, multicentre, placebo-controlled study. British Journal of Rheumatology 35: 7 (JUL 1996): 664-668. SSZ, at a dose of 2.0 g/day appeared to be a safe treatment in patients with psoriatic arthritis. At this dosage, its efficacy was only demonstrated for the pain variable.
5) Psoriatic arthritis is very difficult to treat. I prescribe sulfasalazine 1000 mg T.I.D. plus cephalexin 500 mg twice a day plus Cordran tape on the lesions.