L Carnitine Injection vs. Oral Supplements: Which is More Effective? Katalyst Wellness Injectable L Carnitine 500mg ml (20ml) : Amazon.ca: Health & Personal Care Austin Hodges IFBB PRO L Carnitine is often marketed as a fat burner, but most people don't realize that oral and injectable L Carnitine are not the same. . Oral Instagram Injectable L Carnitine for Slimming: Does It Really Work? National Medical Resources Inc L Carnitine Supplement 500mg 60 Capsules L Tartrate Non GMO Gluten Free Horbaach eBay 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),