Also known as benzodiazepines, Valium, Ativan, Librium, temazepam

Most tranquillisers are prescribed for anxiety and sleeping problems, and suppress mental activity and alertness. They are widely prescribed in the UK. Tolerance develops after two weeks when used as sleeping pills and four months when used against anxiety, but if use continues after tolerance develops it is possible that the user has become psychologically dependent.

Withdrawal effects upon ceasing tranquilliser use after long periods are common, and range from mild to severe. These include: insomnia; anxiety; heightened sensitivity to light, touch, noise and sound; irritability; nausea; vomiting and tremors. In extreme cases convulsions and fits occur which may be life–threatening.

Tranquillisers are often employed by drug users as a means of blunting the effects of anxiety, such as when supplies of a normal drug are unavailable or when coming down from a trip. In non–anxious people they do not produce pleasurable feelings, with the exception of Valium, which may produce mild euphoric feelings. Large quantities of benzodiazepines mixed with alcohol may be dangerous.

Withdrawal symptoms seem particularly noticeable with shorter–acting benzodiazepines such as lorazepam and temazepam. Regular high dose benzodiazepine use in late pregnancy can sometimes result in withdrawal effects in the new–born baby.