Compounded Carnitine (L) Injection Empower Pharmacy L Carnitine Injection vs. Oral Supplements: Which is More Effective? Katalyst Wellness Injectable L Carnitine for Slimming: Does It Really Work? National Medical Resources Inc 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 Burn Bundle MICC & L Carnitine Injections for Fat Burn & Energy Olympia Pharmacy