Technically, any substance other than food that alters our
bodily or mental functioning is a drug. Many people
mistakenly believe the term drug refers only to some sort of medicine or an
illegal chemical taken by drug addicts. They don't realize that familiar substances such as alcohol and tobacco are also drugs. This is why the more
neutral term substance is now used by many physicians and psychologists. The phrase "substance abuse" is often used instead of "drug abuse" to make clear that substances such as alchohol and tobacco can be just as harmfully misused as herion and cocaine.
We live in a society in which the medicinal and social use of substances(drugs) is pervasive: an aspirin to quiet a
headache, some wine to be sociable,coffee to get going in the morning, a cigarette for the nerves. When do these
sociallyacceptable and
apparentlyconstructive uses of a substance become misuses? First of all, most substances taken in excess will produce
negative effects such as poisoning or
intense perceptual distortions. Repeated use of a substance can also lead to physical addiction or substance
dependence. Dependence is marked first by an increased tolerance, with more and more of the substance required to produce the desired effect, and then by the appearance of
unpleasant withdrawal symptoms when the substance is discontinued.
Drugs(substances) that affect the central nervous system and alter
perception, mood, and
behavior are known as psychoactive substances. Psychoactive substances are
commonly grouped according to whether they are stimulants, depressants, or hallucinogens, Stimulants initially speed up or activate the central nervous system, whereas depressants slow it down. Halllucinogens have their primary effect on
perception, distorting and altering it in a variety of ways including producing, hallucinations. These are the substances often called psychedelic(from the Greek word meaning "mind-manifesting") because they seemed to radically alter one's state of consciousness.
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