Trioxsalen bath plus UVA treatment of psoriasis. Plasma concentration of the drug and clinical results

Abstract

Forty-five patients with psoriasis were treated with trioxsalen bath plus UVA. Good or excellent results were obtained in 34 (67%) of the 51 treatments. Trioxsalen plasma concentrations were determined at different stages of the treatment in 10 patients 1 hour after trioxsalen bath, and in 11 patients undergoing treatment for vitiligo 2 hours after ingestion of 0.6 mg trioxsalen per kilogram body weight. The determinations were performed using the glass capillary, gas chromatography, mass spectrometry method, reaching a sensitivity of greater than or equal to 25 pg/ml. The trioxsalen plasma concentrations varied between 12.5 and 0.27 ng/ml after oral ingestion and between approximately 9 ng/ml and less than 25 pg/ml after bath application.