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 6 Benefits of L Carnitine Injections MedHealth 360 Levocarnitine injection is used for..??? The How matters just as much as the What. We put together this step by step guide so you never have to guess what you need,where to inject and the mistakes to avoid. How to Self Administer Subcutaneous & Intramuscular Injections