Terbinafine Nortriptyline

Nortriptyline intoxication secondary to terbinafine has been observed in a woman with a major depressive disorder (214). After rechallenge her serum nortriptyline concentration rose and the serum concentrations of its two hydroxylated metabolites fell. She had a normal genotype for CYP2D6, suggesting that this interaction can occur even in people without reduced CYP2D6 activity. 

TERBINAFINE ANTIDEPRESSANTS- IMIPRAMINE, NORTRIPTYLINE Possible T plasma concentrations ofTCAs Terbinafine strongly inhibits CYP2D6-mediated metabolism of nortriptyline Warn patients to report t side-effects of TCAs such as dry mouth, blurred vision and constipation, which may be an early sign of t TCA levels. In this case, consider i dose of TCA... 

Metabolism by CYP2D6 is of major importance for the hydroxylation of nortriptyline, making it susceptible to competitive inhibition by terbinafine. Nortriptyline intoxication provoked by terbinafine has been reported (72). 

A 37-year-old woman who had been taking amitriptyline 75 mg daily, valproate and olanzapine for 3 years, developed extreme dryness of the mouth, nausea and dizziness shortly after starting to take terbinafine 250 mg daily. Serum levels of amitriptyline and its metabolite nortriptyline rose from just under 400 nanomol/L to over 1800 nanomol/L. Terbinafine was stopped, and the amitriptyline dose reduced to 25 mg daily, but the amitriptyline and nortriptyline levels did not return to baseline for several months. The patient had normal CYP2D6 metaboliser status. ... 

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