Acetyl L Carnitine for Energy Support BioCeuticals Acetyl L. Carnitine Supplement Metabolics Acetyl l Carnitine Pure Prescriptions Carnitine Deficiency: What Is It, Causes, Symptoms, and More Osmosis L carnitine is primarily synthesized in the liver from the amino acids lysine and methionine through a series of four enzymatic reactions, with the liver and kidneys converting the precursor butyrobetaine into active