Did you know L carnitine, a vital amino acid, is naturally produced by your body and found in various foods? While acetyl L carnitine (ALCAR) can be a beneficial supplement for some, most people get L Carnitine, 500 mg, 60 Vegetarian Capsules A quick guide to Lysine H&B Now Liquid L Carnitine 3000mg, 16 Fl oz Did You Know? Some people report a fishy smell after supplementing with L carnitine. This happens because certain gut bacteria convert carnitine to trimethylamine, a malodorous compound found in rotting fish.