Clorazepate Dipotassium. Clorazepate dipotassium, 7-chloro-2,3-dihydro-2-oxo-5-phenyl-1H-1,4-benzodi-azepine-3-carboxylic acid dipotassium salt monohydrate (Tranxene), can be considered a prodrug. Inactive itself, it undergoes rapid decarboxylation by the acidity of the stomach to nordazepam (a major active metabolite of diazepam), which has a long half-life and undergoes hepatic conversion to active oxazepam. Despite the polar character of the drug as administered, because it is quickly converted in the GI tract to an active nonpolar compound, it has a quick onset, overall long half-life, and shares similar clinical and pharmacokinetic properties to chlordiazepoxide and diazepam.
Oxazepam, USP. Oxazepam, 7-chloro-1,3-dihydro-3-hydroxy-5-phenyl-2H-1,4-benzodiazpin-2-one (Serax), is an active metabolite of both chlordiazepoxide and diazepam and can be considered a prototype for the 3-hydroxy benzo-
diazepines. For the stereochemistry of this and other 3-hy-droxy compounds, see the chapter dealing with metabolism. It is much more polar than diazepam. Oxazepam is rapidly inactivated to glucuronidated metabolites that are excreted in the urine. Thus, the half-life of oxazepam is about 4 to 8 hours, and it is marketed as a short-acting anxiolytic. As a result, its cumulative effects with chronic therapy are much less than with long-acting benzodiazepine such as chlor-diazepoxide and diazepam.
Lorazepam, USP. Lorazepam, 7-chloro-5-(2-chloro-phenyl)-3-dihydro-3-hydroxy-2H-1,4-benzodiazepine-2-one (Ativan), is the 2'-chloro derivative of oxazepam. In keeping with overall SARs, the 2'-chloro substituent increases activity. As with oxazepam, metabolism is relatively rapid and uncomplicated because of the 3-hydroxyl group in the compound. Thus, it also has short half-life (2-6 hours) and similar pharmacological activity.
Temazepam. Temazepam, 7-chloro-1,3-dihydro-3-hy-droxy-1-methyl-5-phenyl -2H-1,4-benzodiazepine-2-one (Restoril), also occurs as a minor metabolite of diazepam. It can be visualized as N-methyl oxazepam, and indeed, a small amount of N-demethylation occurs slowly. However, metabolism proceeds mainly through glucuronidation of the 3-hydroxyl group, thus, it is intermediate acting and marketed as a hypnotic said to have little or no residual effect.
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This guide Don't Panic has tips and additional information on what you should do when you are experiencing an anxiety or panic attack. With so much going on in the world today with taking care of your family, working full time, dealing with office politics and other things, you could experience a serious meltdown. All of these things could at one point cause you to stress out and snap.