Viagra, methamphetamine, and HIV risk: results from a probability sample of MSM, San Francisco.

OBJECTIVES To determine the prevalence and factors of Viagra use in combination with crystal methamphetamine and its association with HIV risk behavior in a probability sample of men who have sex with men (MSM). STUDY DESIGN A cross-sectional, random-digit dial telephone survey of MSM in San Francisco conducted between June 2002 and January 2003. RESULTS Of the 1976 MSM, 13.5% used Viagra alone, 7.1% used methamphetamine without Viagra, 9.6% used Viagra with a mood-altering substance (excluding methamphetamine), and 5.1% used Viagra with methamphetamine. Of the MSM using Viagra with methamphetamine, 57% were HIV-infected and 24% of these men reported serodiscordant unprotected insertive intercourse. Viagra used with methamphetamine was independently associated with a higher risk of serodiscordant unprotected insertive intercourse, serodiscordant unprotected receptive intercourse, and a recent diagnosis of a sexually transmitted disease. CONCLUSION MSM who use Viagra with crystal methamphetamine have high prevalence rates of HIV and engage in HIV risk behaviors.