L Carnitine500, 500 mg, 120 Capsules L carnitine supplements can cause a fishy odor in the breath, sweat, and urine. This is likely due to the formation of trimethylamine (TMA). TMA is also responsible for the pungent smell of Eliminate Fishy Smell in Steamed Fish: A Water Guide Acetyl L Carnitine: Benefits and Side Effects Gene Food 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. How to Get Rid of Fishy Smell L Carnitine TikTok