Carnitine (3-hydroxy-4-N-trimethylaminobutyric acid) is an indispensable substance for energy metabolism, especially in tissues dependent on β-oxidation of fatty acids. The main physiologic function of carnitine is the transport of activated long-chain fatty acids across the inner mitochondrial membrane and the reversed transport of any toxic acylgroups originated in mitochondria. L-carnitine also improves metabolism of glucose via stimulation of pyruvate dehydrogenase complex and fructokinase. Its another function is modulation of CoA pool in cells. Carnitine intake is provided mainly by nutrition, the largest portion being in the meat. The organism is also able to supply its needs by an endogenous synthesis in liver, kidneys and brain from amino acids lysine and methionine. Some diseases are connected with carnitine deficiency. It leads to serious health complications. Although the positive results of carnitine supplementation in these patients were found, its use in medicine is still relatively rare. Our duty is to verify these results in other studies and enlarge our therapeutical options with carnitine.

        Key words: carnitine, β-oxidation of fatty acids, carnitine metabolism, carnitine deficiency, carnitine supplementation.