Cytochrome P450 system benzodiazepines

All SSRIs (e.g., Feonard et ah, 1997) and in particular fluoxetine, Fluvosamine and paroxetine are metabolized by hepatic cytochrome P450 enzymes. Therefore, it is important to be aware of the possibility that the therapeutic or toxic effects of other medications metabolized by the cytochrome P450 isoenzyme system can be increased. Substantial inhibition of these isoenzymes converts a normal metabolizer into a slow metabolizer with regard to this specific pathway. Inhibition of the hepatic oxidative isoenzymes has been associated with a reduction, to a varying extent, in the clearance of many therapeutic agents, including the TCAs, several neuroleptics, antiarrhythmics, theophy-lene, terfenadine, benzodiazepines, carbamazepine, and warfarin (for a complete list, see Nemeroff et ak, 1996). 

Ramaekers JG, Ansseau M, MuntjewerfT ND, Sweens JP, O Hanlon JF. Considering the P450 cytochrome system as determining combined effects of antidepressants and benzodiazepines on actual driving performance of depressed ou atients. Int Clin Psychopharmacol (1997) 12, 159-69. 

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