The following is true regarding benzodiazepines

If taken in higher doses it is less toxic than other sedatives Impoant features of Benzodiazepenes Benzodiozepenes are impoant sedatives. Benzodiazepenes act by enhancing presynaptic/postsynaptic inhibition through a specific BZD receptor which is an integral pa of the GABA receptor-C1- channel complex. Benzodiozepenes have a high therapeutic index. - Ingestion of even 50 hyphotic doses does not endanger life there is no less of conciousness (though amnesia occurs) and patient cannot be arousd. Respiration is not so depressed as to need assistance. Benzodiazepenes do not affect respiration or cardiovascular functions. - Higher doses can produce mild respiratory depression and hypotension which can be problematic in patients with respiratory insufficiency and cardiac hemodynamic abnormality. Benzodiazepenes have practically no action on other body systems. - Only on i.v. injection the B.P. falls (may be marked in an occasional patient) and cardiac contractility decreases. Benzodiazepenes cause less distoion of sleep architecture. - Rebound phenomenon on discontinuation of regular use are less marked. Benzodiazepenes do not alter disposition of other drugs by microsomal enzyme induction. - They do not induce liver enzymes. They have lower abuse liability, - Tolerance is mild, psychologial and physical dependence and withdraw! syndroms are less marked. Pharmacokinetics Benzodiazepenes are effective after administration by mouth. The liver metabolizes them usually to inactive metabolites but some compounds produce active metabolites some with long t i/2 whih greatly extends drug action e.g. chlordiazepoxide, clorazepate and diazepam ali form desmethyldiazepam.