Article

Sodium valproate acutely inhibits lamotrigine metabolism.

Wellcome Research Laboratories, Beckenham, Kent.
British Journal of Clinical Pharmacology (Impact Factor: 3.69). 06/1992; 33(5):511-3. DOI: 10.1111/j.1365-2125.1992.tb04079.x
Source: PubMed

ABSTRACT Concomitant administration of sodium valproate (VPA) reduced lamotrigine (LTG) total clearance by approximately 21% and increased elimination half-life and AUC. Reduced elimination occurred acutely within the first hour. Renal elimination of LTG was not impaired. The most probable explanation for this effect is hepatic competition between VPA and LTG for glucuronidation. Volume of distribution and parameters related to absorption, Cmax and tmax were unchanged.

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