Heroin, also known as diamorphine among other names, is an opioid most commonly used as a recreational drug for its euphoric effects. It is used medically in several countries to relieve pain or in opioid replacement therapy. It is typically injected, usually into a vein, but it can also be smoked, snorted, or inhaled.The onset of effects is usually rapid and lasts for a few hours.
Common side effects include respiratory depression (decreased breathing), dry mouth, drowsiness, impaired mental function, constipation, and addiction. Side effects of use by injection can include abscesses, infected heart valves, blood-borne infections, and pneumonia. After a history of long-term use, opioid withdrawal symptoms can begin within hours of the last use. When given by injection into a vein, heroin has two to three times the effect of a similar dose of morphine.It typically comes as a white or brown powder.