Most are powders, usually in capsule form. Used medically to calm people & as sleeping pills. Misusers generally take them by mouth, occasionally with alcohol. They may also inject.
SHORT-TERM USE: Initially may produce sense of relaxation to confused intoxicated state, with poor speech & body control & danger of accidental injury. Depending on dose, effect last 3-6hrs. Large dose can cause unconsciousness, respiratory failure & death. Fatal overdose is ever-present danger as amount which can cause death isn't much more than normal dose. Effects/hazards magnified by alcohol.
LONG-TERM USE: Psychological & physical dependence may develop. Withdrawal symptoms include irritability, restlessness, trembling, faintness, {nausea}, confusion & {delirium}. Sometimes {convulsions}, which may be associated with lasting brain damage. Sudden withdrawal from high doses can be fatal.
Heavy users are also more prone to {bronchitis} & {pneumonia} because cough reflex is depressed. May suffer from {hypothermia} because drug blocks normal responses to the cold. Also risk of repeated accidental overdose. Most of these hazards are increased if drug is injected.
