Nystatin in Psoriasis.

The hypothesis of the role of Candida in the gut for provoking psoriasis was tested by treating 9 males and 6 females having stable psoriasis with 200,000 units of nystatin orally 4 times a day for a minimum of 6 weeks. Intradermal candidin test and throat swab and stool samples for culture of Candida were taken before and twice after (between 4 and 8 weeks) institution of the therapy. Various Candida species isolated before therapy in 11 patients, disappeared after the therapy in 6. In the other 5 the colony counts came down. Only scaling became less in 4 patients. More than 50% clearance was noted in 2 patients. No improvement occurred in 9 patients. No obivous correlation between isolation and disappearance of Candida and persistence or clearance of lesions was observed. Immediate (Type-1) hypersensitivity response to candidin was positive in only 3 patients. Immediate hypersensitivity to Candida antigens -or its metabolic products does not appear to have any role in the pathogenesis of psoriasis.