Benzodiazepines are antianxiety drugs that help relieve nervousness, tension, and other symptoms by slowing the central nervous system. The group of drugs known as benzodiazepines includes alprazolam (Xanax), chlordiazepoxide (Librium), diazepam (Valium), and lorazepam (Ativan). These medicines take effect fairly quickly, usually within one hour after they are taken. They are available only with a doctor's prescription, and should not be used to relieve the nervousness and tension of normal everyday life. The recommended dosage depends on the type of benzodiazepine, its strength, and the condition for which it is being taken.

While anxiety is a normal response to stress, some people have unusually high levels of anxiety that can interfere with everyday life. For these people, benzodiazepines can help bring their feelings under control. The medicine can also relieve troubling symptoms of anxiety, such as pounding heartbeat, breathing problems, irritability, nausea, and faintness.

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