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 Fish Odor Carnitine TikTok Acetyl L Carnitine Amazon: What to Know Before You Buy L Carnitine: Benefits, Uses, Side Effects, and More Carnitine Deficiency: What Is It, Causes, Symptoms, and More Osmosis signOut