Inpharma 1305 - 15 Sep 2001

■ The serum concentration of olanzapine isincreased by fluvoxamine, but not sertraline, sayresearchers from Germany. In this study, the ratio ofthe serum concentration (ng/ml):daily dose (mg/day)of olanzapine was assessed in 134 patients receivingolanzapine alone, and 31 patients who receivedolanzapine in combination with sertraline 50–150mgor fluvoxamine 50–150mg, all once daily.* The meanserum concentration:daily dose ratio of olanzapinewas significantly higher in patients who were alsoreceiving concomitant fluvoxamine, compared withthose receiving olanzapine only (5.3 vs 2.3).Concomitant administration of sertraline did notsignificantly alter the mean serum concentration:dailydose ratio of olanzapine. The researchers concludethat the combination of fluvoxamine and olanzapine‘should be used cautiously and controlled bytherapeutic drug monitoring’.* One patient received fluvoxamine 300mg.

Weigmann H, et al. Fluvoxamine but not sertraline inhibits the metabolism ofolanzapine: evidence from a therapeutic drug monitoring service. TherapeuticDrug Monitoring 23: 410-413, Aug 2001 800879372

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Inpharma 15 Sep 2001 No. 13051173-8324/10/1305-0001/$14.95 Adis © 2010 Springer International Publishing AG. All rights reserved