Substance use disorders, which are problematic patterns of using alcohol or another substance, such as crack cocaine, methamphetamine (“meth”), amyl nitrite (“poppers”), prescription opioids, and heroin, are closely associated with HIV, AIDS, and other sexually transmitted diseases.
Injection drug use (IDU) can be a direct route of HIV transmission if people share needles, syringes, or other injection materials that are contaminated with HIV. However, drinking alcohol and ingesting, smoking, or inhaling drugs are also associated with increased risk for HIV. These substances alter judgment, which can lead to risky sexual behaviors (e.g., having sex without a condom, having multiple partners) that can make people more likely to get and transmit HIV.
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