Temazepam Rifampicin

BZDs, NOT LORAZEPAM, OXAZEPAM, TEMAZEPAM RIFAMPICIN 1 BZD levels Induction of CYP3A4-mediated metabolism Watch for poor response to these BZDs consider increasing the dose, e.g. diazepam or nitrazepam 2-3-fold... 

Other drugs are metabolised by Phase II synthetic reactions, catalysed typically by non-microsomal enzymes. Processes include acetylation, sulphation, glycine conjugation and methylation. Phase II reactions may be affected less frequently by ageing. Thus according to some studies, the elimination of isoniazid, rifampicin (rifampin), paracetamol (acetaminophen), valproic acid, salicylate, indomethacin, lorazepam, oxazepam, and temazepam is not altered with age. However, other studies have demonstrated a reduction in metabolism of lorazepam, paracetamol (acetaminophen), ketoprofen, naproxen, morphine, free valproic acid, and salicylate, indicating that the effect of age on conjugation reactions is variable. 

Rifampicin, and presumably other enzyme inducers, reduces concentrations of zolpidem, zopiclone, and buspirone (SEDA-22, 42). Drugs that are solely glucuroni-dated (lorazepam, oxazepam, and temazepam) are not affected. 

Arachidonic acid, benzo[a]pyrene, carbamazepine, clozapine, cyclophosphamide, S) and (R)-ibuprofen, omeprazole, paclitaxel, progesterone, retinoic acid, sulfadiazine, temazepam, testosterone, tienilic acid, trimethoprim, (J2)-warfarin, zidovudine Sulfafenazole Rifampicin... 

A study found that the pharmacokinetics of temazepam were unchanged by rifampicin." ... 

Rifampicin is a potent liver enzyme inducer, which increases the metabolism of several benzodiazepines and the non-benzodiazepine hypnotics, zaiepion, zoipidem and zopiclone, thereby decreasing their levels. The metabolism of midazolam by the cytochrome P450 isoenzyme CYP3A4 in both liver and gut is affected. The enzyme inducing effects of rifampicin seem to predominate if isoniazid (an enzyme inhibitor) is also present. Temazepam undergoes glucuronidation and is therefore unaffected by rifampicin. 

Those benzodiazepines that, like temazepam, undergo glucuronidation (e.g. lorazepam, oxazepam) are not expected to be affected by rifampicin and may be useful alternatives. 

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See also in sourсe #XX -- [ ]

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