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 How Fast Does L Carnitine Work? Real Results Guide LABRADA INDIA The bright and the dark sides of L carnitine supplementation: a systematic review Journal of the International Society of Sports Nutrition Springer Nature Link Injectable L Carnitine: Does It Really Work for Fat Loss? L Carnitine. Fat burning hero or just another hype supplement? If weight loss is your goal, L Carnitine might support your journey, but it's not a magic fix Here's what it actually does