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 Carnitine Deficiency: What Is It, Causes, Symptoms, and More Osmosis Do you or someone you love smell like fish? It could be Fish Odor Syndrome! #fishodorsyndrome #fishy #fishysmell #fishodor Can Acetyl L Carnitine Help Clear Brain Fog and Fatigue in Long COVID and ME CFS? RTHM Does Carnitine Cause Body Odor? Lume Deodorant