Injectable vs Oral L Carnitine: Which Works Better? AWP LCarnitine Injections Energy & Fat Metabolism Support TX 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 1 GM 5 ML ( L CARNITINE ) 5 X 5 ML IV USE AMPOULES Levocarnitine Injection: Package Insert Prescribing Info L CARNITINE Why we chose to bring this injection on it pairs GREAT with our weight loss program, is a stellar stand alone injection, and is absorbed much more effectively as injection. AND,