Heroin, also known as diacetylmorphine and diamorphine among other names, is a morphinan opioid substance synthesized from the dried latex of the Papaver somniferum plant; it is mainly used as a recreational drug for its euphoric effects. Medical-grade diamorphine is used as a pure hydrochloride salt. Various white and brown powders sold illegally around the world as heroin are routinely diluted with cutting agents. Black tar heroin is a variable admixture of morphine derivatives—predominantly 6-MAM (6-monoacetylmorphine), which is the result of crude acetylation during clandestine production of street heroin. Heroin is used medically in several countries to relieve pain, such as during childbirth or a heart attack, as well as in opioid replacement therapy.