Colloidal silicic acid for the treatment of psoriatic skin lesions, arthropathy and onychopathy. A pilot study.

In a randomized, double-blind study, patients with chronic plaque-type psoriasis were either treated with 30 ml colloidal silicic acid gel, orally, daily, and topically with the same gel (n = 15), or were treated identically with placebo gel (n = 15) for 3 months. One stable psoriatic lesion on the knee or elbow was treated topically and followed throughout the study. Five patients in the treated group and seven controls had psoriatic arthropathy and 11 treated patients and 12 controls had psoriatic onychopathy. Three treated patients and six controls withdrew because of skin irritation or lack of efficacy. In the treated group there were clear improvements in scaling, induration and erythema after treatment. The nail changes were cured in five of 10 evaluable patients in the treated group and joint pain was reduced by almost half in the four evaluable patients with arthropathy. There were no such improvements in the placebo group.