Substance Abuse (Depressants or Sedative-Hypnotic Drugs)

What Is It?

Sedative-hypnotic drugs — commonly called "depressants" — slow down or "depress" the activity of the brain. The best known are barbiturates (Amytal, Nembutal, Seconal, phenobarbital) and benzodiazepines (Ativan, Halcion, Librium, Valium, Xanax, Rohypnol). Other drugs in this group include chloral hydrate (which when mixed with alcohol was once known as "knockout drops" or a "Mickey Finn"), glutethimide (Doriden), methaqualone (Quaalude, Sopor, "ludes") and meprobamate (Equanil, Miltown and other brand names).

Although alcohol is also a depressant, alcohol is so common that health experts classify alcohol-related problems separately.

Regular use of these drugs often leads to "drug tolerance." That is, the body adjusts to them and it takes a higher and higher dose to achieve the desired effect. Dependence also can develop, meaning withdrawal symptoms will occur if the drug is suddenly stopped.

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