Trimethylaminuria (Fish Odor Syndrome or TMAU) TMAO (Trimethylamine oxide) biocrates life science Exploring Trimethylaminuria: Genetics and Molecular Mechanisms, Epidemiology, and Emerging Therapeutic Strategies 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