Taken in high doses, nutmeg can be quite intoxicating, partly because it's similar in chemical makeup to MDMA. Nutmeg causes symptoms such as stupor, drowsiness, delirium and sleep. Many prison inmates have known about it and used it for years, which is why most prisons have banned the use of this spice! About 14 grams (two tablespoons) taken by mouth cause a rather unpleasant, dreamlike "trip". Other symptoms include a rapid heartbeat, dry mouth, and thirst. Agitation, apprehension, and a sense of impending doom may last about 12 hours, with a sense of unreality persisting for several days. Nutmeg contains five to 15 per cent myrista oil, which is responsible for the physical effects. About four per cent is Myristicin, which is structurally similar to mescaline. (Mace, the exterior covering of the Nutmeg seed, also contains the hallucinogenic compound myristicin). Elemicin is another potent psychoactive ingredient in nutmeg. Similar to SSRI antidepressants such as Prozac, Myristicin blocks the release of serotonin from brain neurones. Scientists believe that once the substance enters the body it's converted to methylenedioxymethamphetamine (MDMA) -- ecstasy.

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Side Note - Heroin is often cut with as nutmeg, sucrose, starch, caffeine, chalk, powdered milk, flour, talcum powder.