Top L Carnitine Supplements GNC When Should You Take L Carnitine? MuscleTech 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 What's the Difference Between CLA and Carnitine? L Carnitine helps your body turn fat into fuel improving energy, endurance, and recovery. Combine it with consistent training and a clean diet for real results! . . . . #LCarnitine #