Injectable L carnitine vs oral? For me, absorption, fewer GI issues, & energy performance gains make injections the winner. #LCarnitine #Injectable #Bioavailability #MetabolicHealth #EnergyBoost Liquid L Carnitine Energy CARNITOR (levocarnitine) Injection 1 g per 5 mL vial For Intravenous Use Only. L Carnitine is often marketed as a fat burner, but most people dont realize that oral and injectable L Carnitine are not the same..Oral L Carnitine has poor absorption (only 20% bioavailability), L Carnitine Dosage for Erectile Dysfunction: What the Evidence Shows and How to Use It Safely L Carnitine: Benefits, Side Effects, FAQ, Sources, and Dosage