Oral Acetyl- l -Carnitine Therapy and Insulin Resistance

Abstract

To the Editor: We reported recently that oral acetyl-l-carnitine supplementation improved hypertension in patients at increased cardiovascular risk, as well as whole body glucose use in those with advanced insulin resistance, but not yet diabetes mellitus.1 These findings led us to suggest that acetyl-l-carnitine treatment corrects a relative carnitine deficiency in this population. However, in a recent letter to the editor, Muniyappa2 states that oral l-carnitine supplementation cannot achieve the plasma carnitine levels required to increase skeletal muscle carnitine concentration and improve insulin sensitivity. He refers to previous studies suggesting an insulin-sensitizing effect of intravenous l-carnitine that he reports …