Heroin or diamorphine (INN) (colloquially referred to as junk, babania, horse, golden brown, smack, black tar, H, big H, lady H, dope, skag, juice, diesel, etc.) is an alkaloid opioid. Heroin is the 3,6-diacetyl derivative of morphine (hence diacetylmorphine) and is synthesised from it by acetylation. The white crystalline form is commonly the hydrochloride salt, diamorphine hydrochloride. It is highly addictive. ...