Slang Smack, Horse, Mud, Brown Sugar, Junk, Black Tar, Big H, Dope, Skag
Heroin affects your brain. Heroin enters the brain quickly. It slows down the way you think, slows down reaction time, and slows down memory. This affects the way you act and make decisions.
Heroin affects your body. Heroin poses special problems for those who inject it because of the risks of HIV, hepatitis B and C, and other diseases that can occur from sharing needles. These health problems can be passed on to sexual partners and newborns.
Heroin is super-addictive. Heroin is highly addictive because it enters the brain so rapidly. It particularly affects those regions of the brain responsible for producing physical dependence.