A Review of Valproic Acid–Induced Carnitine Deficiency and Replacement

Abstract

Objective:

To review valproic acid–induced carnitine deficiency and subsequent carnitine replacement.

Data Sources:

Articles indexed in MEDLINE from 1966 to May 2000, as well as other published works and standard references.

Data Extraction:

Studies investigating clinical epidemiologic and pathologic evidence of the role of valproic acid–induced carnitine deficiency and double-blind clinical trials evaluating the effectiveness of carnitine replacement with anticonvulsant therapy are presented.

Data Synthesis:

Clinical epidemiologic and pathologic studies provide evidence of valproic acid–induced carnitine deficiency. There is no clear consensus for providing carnitine supplementation to all patients taking valproic acid — It is only indicated for children with valproic acid–induced hepatotoxicity and those with valproic acid overdose.

Conclusions:

There is evidence that implicates valproic acid in inducing carnitine deficiency. Patients should be evaluated clinically for signs and symptoms of carnitine deficiency before beginning supplementation. Currently, carnitine supplementation should be reserved for children with valproic acid–induced hepatotoxicity and valproic acid overdose until the results of further clinical studies are available.