Chlordiazepoxide (trade name Librium) is a sedative and hypnotic medication of the benzodiazepine class. Chlordiazepoxide is indicated for the management of anxiety disorders or for the short-term relief of symptoms of anxiety, withdrawal symptoms of acute alcoholism, and preoperative apprehension and anxiety. Anxiety or tension associated with the stress of everyday life usually does not require treatment with an anxiolytic. The effectiveness of Librium in long-term use, that is, more than 4 months, has not been assessed by systematic clinical studies. Chlordiazepoxide acts on benzodiazepine allosteric sites that are part of the GABAA receptor/ion-channel complex and this results in an increased binding of the inhibitory neurotransmitter GABA to the GABAA receptor thereby producing inhibitory effects on the central nervous system and body similar to the effects of other benzodiazepines. Chlordiazepoxide act via micromolar benzodiazepine binding sites as Ca2+ channel blockers and significantly inhibit depolarization-sensitive Calcium uptake in animal nerve terminal preparations. The withdrawal of chlordiazepoxide during pregnancy and breastfeeding is recommended, as chlordiazepoxide rapidly crosses the placenta and also is excreted in breast milk. Chlordiazepoxide is a long-acting benzodiazepine drug. The half-life of Chlordiazepoxide is 5 – 30 hours but has an active benzodiazepine metabolite (desmethyldiazepam), which has a half-life of 36 – 200 hours. The necessity of discontinuing therapy because of undesirable effects has been rare. Drowsiness, ataxia and confusion have been reported in some patients — particularly the elderly and debilitated. While these effects can be avoided in almost all instances by proper dosage adjustment, they have occasionally been observed at the lower dosage ranges. In a few instances syncope has been reported.