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 Healthvit L Carnitine L Tartrate 500 mg Supplement Acetyl L Carnitine Alpha Lipoic Acid Erectile Dysfunction Propionyl L Carnitine for Erectile Dysfunction: What the Evidence Shows and How to Approach It