Carnitine, gamma-trimethyl-beta-hydroxybutyrobetaine, is a small molecule widely present in all cells from prokaryotic to eukaryotic. It is an important
element in the beta-oxidation of
fatty acids. A lack of
carnitine in
hemodialysis patients is caused by insufficient
carnitine synthesis and particularly by the loss through dialytic membranes, leading in some patients to
carnitine depletion with a relative increase of esterified forms. The authors found a decrease in plasma-
triglyceride and increase of
high-density lipoprotein cholesterol (HDL-Chol) in dialysis patients during
carnitine treatment. Many studies have shown that
L-carnitine supplementation leads to improvements in several complications seen in uremic patients, including cardiac complications, impaired exercise and functional capacities, muscle symptoms, increased symptomatic intradialytic
hypotension, and
erythropoietin-resistant
anemia, normalizing the reduced
carnitine palmitoyl
transferase activity in red cells. In addition,
carnitine supplementation may improve
protein metabolism and
insulin resistance. Recently,
carnitine supplementation has been approved by the US Food and Drug Administration not only for the treatment, but also for the prevention of
carnitine depletion in dialysis patients. Regular
carnitine supplementation in
hemodialysis patients can improve their lipid metabolism,
protein nutrition,
antioxidant status, and
anemia requiring large doses of
erythropoietin, It also may reduce the incidence of intradialytic
muscle cramps,
hypotension,
asthenia,
muscle weakness, and
cardiomyopathy.