Alternative therapies are known to be employed by dermatology patients. This study investigates the use of alternative medical treatments for psoriasis and the sociodemographic variables, conventional medical treatment, and psoriasis disease severity. Our study population consisted of 578 university dermatology clinic patients with psoriasis and data was analyzed from 317 (55 percent) questionnaire respondents. The majority of our sample were women (57 percent) and nonwhites represented 8 percent of our sample. Psoriasis severity was measured using the validated Self-Administered Psoriasis Area and Severity Index. Alternative medicine was used by 62 percent of respondents. Excluding sunlight and nonprescription tanning equipment, 51 percent used one or more of the remaining alternative therapeutic modalities. The psoriasis severity was worse in those who had tried herbal remedies, vitamin therapy, and dietary manipulation. With the exception of vitamin therapy, we observed no association between the intensity of conventional medical treatment and alternative treatment. The present or prior use of herbal remedies was correlated with the use of vitamin therapy and sunbathing, and dietary interventions were significantly correlated with vitamin therapy. Of the 113 (36 percent) who had used nonprescription tanning equipment for their psoriasis, 68 percent believed this modality was effective. We found that alternative medical therapies were widely utilized by subjects participating in this study. Clinicians need to continue to be aware of nonallopathic remedies employed by their patients to discover useful information about future therapies and to monitor for adverse effects.