Use of methamphetamine (often called crystal meth) by gay men is associated with unprotected sex and HIV seroconversion, according to two recently published American studies.

Investigators from the Multicenter AIDS Cohort Study (MACS) found that gay men who used methamphetamine and poppers during sex, and who had unprotected sex with five or more partners had an extremely high risk of contracting HIV. Their findings are published in the May 1st edition of the Journal of Acquired Immune Deficiency Syndromes.