Alprazolam does not inhibit the metabolism of nortriptyline in depressed patients or inhibit the metabolism of desipramine in human liver microsomes.
In 10 patients treated with nortriptyline, the steady-state plasma concentrations of the parent drug and the active 10-hydroxy metabolite were very similar before and during concomitant treatment with alprazolam (0.5 mg orally t.i.d.). In human liver microsomes the 2-hydroxylation of desipramine was not inhibited by alprazolam. The absence of an inhibition by alprazolam on the hydroxylations of nortriptyline in vivo and of desipramine in vitro indicates that alprazolam is not metabolized by the debrisoquine hydroxylase.
Bertilsson
L
L
Department of Clinical Pharmacology, Karolinska Institute, Huddinge Hospital, Sweden.
Aberg-Wistedt
A
A
Lidén
A
A
Otani
K
K
Spina
E
E
D000328:Adult; D000525:Alprazolam / Q000494:pharmacology*; D003866:Depressive Disorder / Q000378:metabolism*; D003891:Desipramine / Q000378:metabolism*; D004347:Drug Interactions; D005260:Female; D006801:Humans; D006900:Hydroxylation; D066298:In Vitro Techniques; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism*; D008875:Middle Aged; D009661:Nortriptyline / Q000378:metabolism*
D009661:Nortriptyline; D003891:Desipramine; D000525:Alprazolam