Heroin injection. Heroin being injected into the arm of a man in the company of a small boy. The man has used strapping around his arm as a tourniquet to make his veins stand out. Beside him is the foil that the drug came in and a candle and spoon for heating and dissolving the drug in water. Heroin (diacetyl morphine) is a white or brownish powder. It can be smoked or sniffed but in this case it has been dissolved in water and is being injected into a vein. Heroin produces feelings of warmth, drowsiness and lack of concern for outside events. Long term use causes tolerance and dependence (addiction).