Stabilizing the enzyme in fish odor syndrome L Carnitine is an amino acid that supports weight loss as it is a fat burning supplement. L Carnitine Push is a direct and quick IV infusion procedure that can be done on a weekly Get Rid of Fishy L Carnitine Smell: Essential Fixes Tonum 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 L Carnitine: Does it help with weight loss?