Heroin (diacetylmorphine or morphine diacetate (INN)), also known as diamorphine (BAN), is an opiate analgesic synthesized by C.R. Alder Wright in 1874 by adding two acetyl groups to the molecule morphine found in the opium poppy. It is the 3,6-diacetyl ester of morphine, and functions as a morphine prodrug (meaning that it is metabolically converted to morphine inside the body in order for it to work). When used in medicine it is typically used to treat severe pain, such as that resulting from a heart attack or a severe injury. The name 'heroin' is only used when being discussed in its illegal form. When it is used in a medical environment, it is referred to as Diamorphine. The white crystalline form considered 'pure heroin' is usually the hydrochloride salt, diacetylmorphine hydrochloride. Illegally supplied heroin however is more often in freebase form, dulling the sheen and consistency to a matte-white powder.
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