Heroin

Heroin, also known as diamorphine, is an opiate drug that is synthesized from morphine, a naturally occurring substance extracted from the seed pod of the Asian opium poppy plant. It can be injected, snorted/sniffed, or smoked, all of which rapidly deliver the drug to the brain. Once in the brain it is converted to morphine and binds to receptors known as opioid receptors - primarily those involved in the perception of pain and in reward - often resulting in addiction.