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. Carnitine Deficiency: What Is It, Causes, Symptoms, and More Osmosis Carnitine Blend Rootcology Amazon.com: Nutricost Acetyl L Carnitine (ALCAR) 500mg, 180 Capsules, 180 Servings Non GMO and Gluten Free, 1 Capsule per Serving : Everything Else