Injectable L Carnitine: What It Is, How It Works, and Who Should Use It Mesotherapy Cocktails, Exosomes Regenerative Skin Boosters 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 L Carnitine L carnitine is a naturally occurring amino acid structure that is made in the human brain, liver, and kidneys. L carnitine plays a critical role in energy production, as it converts fat into energy. What Is L Carnitine: Benefits, Dosage, And Side Effects LiveLeanTV