Voriconazole
Carisoprodol (Soma) Interactions
NOTE: Carisoprodol is extensively metabolized and is a significant substrate of CYP2C19 isoenzymes. The formation of meprobamate (active metabolite of carisoprodol) is catalyzed by CYP2C19.
Carisoprodol is metabolized to meprobamate, a significant CNS depressant. Carisoprodol can cause additive CNS depression if used concomitantly with other CNS depressants such as anxiolytics, sedatives, and hypnotics, benzodiazepines, barbiturates, buprenorphine, butorphanol, nalbuphine, opiate agonists, pentazocine, tramadol, tricyclic antidepressants, phenothiazines, dronabinol, THC, ethanol, or sedating H1-blockers. The phytomedicinal herbs valerian, Valeriana officinalis or kava kava, Piper methysticum may also interact in this fashion. There may be additive effects of sedation and dizziness, which can impair the ability to undertake tasks requiring mental alertness. In addition, respiratory depression may occur with concurrent use of carisoprodol with CNS depressants that depress respiratory function (e.g., barbiturates, benzodiazepines, opiate agonists). Dosage adjustments of carisoprodol and/or the concurrent CNS depressant may be necessary.
Carisoprodol is extensively metabolized and is a significant substrate of CYP2C19 isoenzymes. The formation of meprobamate (active metabolite of carisoprodol) is catalyzed by CYP2C19. Clinically significant interactions have not been documented involving CYP2C19 inhibitors and carisoprodol. Theoretically, CY2C19 inhibitors could increase carisoprodol plasma levels, with potential for enhanced CNS depressant effects. Examples of CYP2C19 inhibitors include: bortezomib, cimetidine, delavirdine, efavirenz, felbamate, fluoxetine, fluvoxamine, isoniazid, INH, modafinil, omeprazole, oxcarbazepine, ticlopidine, and voriconazole. This list is not inclusive of all CYP2C19 inhibitors.
Carisoprodol is extensively metabolized and is a significant substrate of CYP2C19 isoenzymes. The formation of meprobamate (active metabolite of carisoprodol) is catalyzed by CYP2C19. If carisoprodol (CYP2C19 substrate) is combined with an inducer of hepatic enzymes, the potential exists for increased metabolism of carisoprodol. However, the clinical significance of induced carisoprodol metabolism is unknown. Theoretically, carisoprodol plasma concentrations could be decreased, and meprobamate (active metabolite) plasma concentrations could be increased. Examples of potential CYP2C19 enzyme inducers include: barbiturates such as phenobarbital; ethotoin, phenytoin or fosphenytoin; rifampin, rifapentine, and rifabutin.
[ Last revised: 3/30/2005 12:05:00 PM ]
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