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 supplementation beneficial for reducing waistline and blood pressure Meta analysis L Carnitine Benefits, Uses, Dosage, Foods, Side Effects Dr. Axe The adverse effects of long term l carnitine supplementation on liver and kidney function in rats L Liu, D M Zhang, M X Wang, C Y Fan, F Zhou, S J Wang, L D Kong, 2015 L Carnitine: Benefits, Side Effects, FAQ, Sources, and Dosage