"Transmission of HIV and hepatitis B and C can be consequences of methamphetamine abuse. The intoxicating effects of methamphetamine, regardless of how it is taken, can also alter judgment and inhibition and lead people to engage in unsafe behaviors, including risky sexual behavior. Among abusers who inject the drug, HIV and other infectious diseases can be spread through contaminated needles, syringes, and other injection equipment that is used by more than one person."
Source
National Institute on Drug Abuse, InfoFacts: Methamphetamine (Rockville, MD: US Department of Health and Human Services), Revised: July 2009.
http://www.drugabuse.gov/publ…
