MODEL RELEASED. Heroin injection. Man injects heroin into his arm while a woman holds a tourniquet made from a belt. The tourniquet makes the man's veins stand out. Heroin (diacetyl morphine) is a white or brownish powder. It can be smoked or sniffed but here it has been dissolved in water and is being injected into the blood- stream. Heroin produces feelings of drowsiness, warmth and lack of concern for outside events. Long term use causes tolerance (larger amounts of drug are needed to have the same effect) and addiction. Infections such as hepatitis B virus and HIV can be spread when addicts share needles. Death commonly occurs from accidental overdose.