Heroin---Summerian texts refer to the opium poppy, from which morphine, father of heroin, is derived, as the "joy plant". Often referred to as 'Smack, 'Junk', 'Skag', 'H', 'Brown', 'Horse', 'Harry', or 'Boy', heroin is a highly addictive drug that affects the brain's pleasure systems and screws up it's ability to perceive pain.
             It is mainly believed that Arab traders took opium to China in about the 7th or 8th century A.D. It was used there as a medicine until it was realized that it could be smoked in the 17th century. Heroin was created in 1874 and was marketed as a safe and non-addictive alternative to morphine. It was quickly discovered though, that heroin also produced dependancy quickly in some patients. Opiates and heroin were made illegal in 1920 with the Dangerous Drugs Act.
             As you may have figured out, heroin comes from the family of drugs called Opiates, the name of which, of course, comes from the original drug in the classification, opium. Opium is dried poppy sap, which can be refined into morphine; an effective painkiller, and used also in many cough medicines and diarrhea treatments. Though some more chemical treatment, "semi-synthetic opiates" like heroin are made.
             All addictive drugs have two things in common. First, they produce a mainly pleasurable affect. Then it's followed by an awful unpleasant effect. Heroin, and other Opiates, imitate the certain chemicals in our brain that block pain and arouse a feeling of happiness and just "feeling good". Those chemicals are naturally produced when we exercise, have sex, laugh, etc...
             But, unlike the happy chemicals we produce in our brain, a tolerance is built up to heroin and the similar drugs to that it takes more and more to get the good feeling back, while the lows get lower and lower. When you fail to take the heroin, nasty withdrawal symptoms occur.
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