In this alert, health professionals are notified of a labeling change regarding unapproved use of oral formulations of levocarnitine in End Stage Renal Disease (ESRD) patients. Sigma-Tau Pharmaceuticals received approval from the FDA on December 15, 1999 to market Carnitor Injection for the prevention and treatment of carnitine deficiency in patients with ESRD who are undergoing dialysis.

The FDA web site has the retyped text of a letter from Sigma Tau Pharmaceuticals concerning this labeling change.

The problem is that major metabolites are formed following oral administration. These metabolites accumulate in dialysis patients since they can not be efficiently removed by the kidneys. This causes increased amounts of nitrogenous waste to be removed in the dialysis procedure, possible neurophysiologic effects, and the development of 'fishy odor' syndrome. This does not occur to the same extent following IV administration.

Here is the revised label for Carnitor.