American Regent Introduces Levocarnitine Injection, USP; FDA Approved, "AP" Rated, and Therapeutically Equivalent to Carnitor 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 injections for boosted daily energy 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, Is Injectable L Carnitine Safe? Weight Wise Weight Loss Center