PDF) [L carnitine treatment and fish odor syndrome: an unwaited adverse effect]. Trimethylaminuria (Fish Odor Syndrome or TMAU) Acetyl L Carnitine Erectile Dysfunction: Evidence and Practical Advice L Carnitine for Erectile Dysfunction: What the Evidence Shows and How to Use It Does Carnitine Cause Body Odor? Lume Deodorant 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.