L Carnitine Benefits for Fat Burning and How to Use ICONFIT Amazon.com: NOW Foods Supplements, L Carnitine 1,000 mg, Purest Form, Amino Acid, Fitness Support*, 100 Tablets : Health & Household 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 Unlock Peak Performance & Fertility with L Carnitine! Did you know that injectable L Carnitine is a game changer compared to oral supplements? While oral L Carnitine has low bioavailability (only ~14 18%