These experiments have included anecdotal studies of human drug addicts and alcoholics treated with acupuncture; studies of opiate addicted animals; placebo-design studies of human heroin, cocaine, and alcohol users; and studies comparing acupuncture and methadone detoxification protocols. Other studies have examined acupuncture's analgesic effects, as well as links between acupuncture and endogenous opiate peptide (EOP) production and between EOP and analgesia, positive moods, and alleviation of opiate withdrawal symptoms. Controlled research of acupuncture as a method promoting smoking cessation has had mixed results which are difficult to interpret due to various methodological problems. 112 references