The Columbia Encyclopedia, Sixth Edition. 2001-07.
hypnotic drugs
drugs that induce sleep, sometimes called soporifics. In general, hypnotics are central nervous system depressants. Alcohol, laudanum (see opium), bromide salts, and herbs such as valerian have been used as hypnotics. Barbiturates and benzodiazepines are frequently prescribed hypnotics. Smaller doses of these same drugs may be used as sedatives.