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 CARNITOR (levocarnitine) Injection 1 g per 5 mL vial For Intravenous Use Only. How To Give a Subcutaneous (SubQ or SQ) Injection OncoLink L Carnitine Injectable Factor Health MD Subcutaneous Injection: What It Is and How to Give One Product Spotlight! L Carnitine injections infusions and the benefits thereof!