The Role of Carnitine in the Male Reproductive System NG 2004 Annals of the New York Academy of Sciences Wiley Online Library Carnitine: Genetic Variants Affecting Mitochondrial Energy and Health The Ultimate Showdown: L Carnitine vs. Acetyl L Carnitine Ultimate Sup Structure of L carnitine and acetyl L carnitine. Download Scientific Diagram L Carnitine injection is recommended at 1 ampule every 2 3 days for best results. The L Carnitine is taken intravenously either by normal injection or using a butterfly needle. After taking this L Carnitine, you