Narcotics
Narcotics, term originally applied to all compounds that produce insensibility to external stimuli through depression of the central nervous system, but now applied primarily to the drugs known as opiates—compounds extracted from the opium poppy and their chemical derivatives. Also classed as narcotics are the opioids, chemical compounds that are wholly synthesized, but which resemble the opiates in their actions. The most important attribute of narcotics is their capacity to decrease pain, not only by decreasing the perception of pain, but also by altering the reaction to it. Although they do have sedative properties when used in large doses, they are not used primarily for sedation. The major constituent of opium and the prototype of all narcotic analgesics is morphine, which was isolated and chemically analyzed by the German apothecary F. W. A. Setürner between 1805 and 1817. Other narcotics used in the U.S. are meperidine (trade name Demerol), codeine, and propoxyphene (trade name...