Chlordiazepoxide. See Librium

Several of the most-used benzodiazepine tranquillizers seem to act as the metabolic product, nordazepam (3.47), which has the full therapeutic action of the starting materials, and acts faster. Thus diazepam (12.95) ( Valium ) loses 1-Me, chlordiazepoxide ( Librium ) loses 4-0 and hydrolyses 2-MeNH- to=0, whereas clorazepate ( Tranxene ) loses 4-CO2, and in each case nordazepam is the product. While the latter is available for prescribing, clinical experience with the pro-drugs is greater moreover they have very different pharmacokinetics, diazepam being absorbed quickly and chlordiazepoxide slowly from the gastrointestinal tract. See further Section 12.7 Garattini, Mussini and Randall (1973), Nicholson a/. (1976), and Hollister (1978). 

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