L Carnitine Injection Levocarnitine IV L Carnitine is Underrated. New Meta Review Reminds Us Why. Injectable L Carnitine for Slimming: Does It Really Work? National Medical Resources Inc Injectable L carnitine works better than oral because it goes straight into your bloodstream, giving almost 100% of absorption versus only 518% with capsules or liquid. , Oral L carnitine can take 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 Injection Levocarnitine IV