Liquid L Carnitine 3000: Metabolism & Energy Support 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 ACETYL L CARNITINE STRONG LIQUID vial 25 ml L Carnitine vs Pre Workout: Which Supplement Should You Take? L Carnitine Uses & Benefits Explained: A Complete Guide The Science of Good Health