Trimethylaminuria (TMAU), also known as fish odor syndrome or fish malodor syndrome, is a rare metabolic disorder that causes a defect in the normal production of an enzyme named flavin-containing monooxygenase 3 (FMO3). When FMO3 is not working correctly or if not enough enzyme is produced, the body loses the ability to properly convert trimethylamine (TMA) from precursor compounds in food digestion into trimethylamine oxide (TMAO), through a process called N-oxidation. Trimethylamine then builds up and is released in the persons sweat, urine, and breath, giving off a strong fishy odor or strong body odor. Primary trimethylaminuria is caused by genetic mutations that affect the FMO3 function of the liver. A variant of TMAU (secondary trimethylaminuria or TMAU2) is an acquired form of TMAU where there is no genetic cause, yet excessive TMA is secreted. TMAU2 can be caused by a range of issues, including a precursor overload (ingesting too many precursors), hormonal issues related to menstrual cycles, liver damage, and liver and kidney failure. It is hypothesised that intestinal dysbiosis may cause temporary TMAU2 symptoms, however there is no direct evidence of this in a scientific study. Metabolic pathway
Trimethylamine enters the body via the consumption of certain foods and supplements. When food is consumed that contains TMA and/or TMAO (predominately seafood; saltwater fish, shellfish, seaweed and kelp), TMAO is converted by bacteria in the lower gastrointestinal tract (gut) into TMA.
Labetalol is a medication used to treat high blood pressure and in long term management of angina. This includes essential hypertension, hypertensive emergencies, and hypertension of pregnancy. In essential hypertension it is generally less preferred than a number of other blood pressure medications. It can be given by mouth or by injection into a vein.Common side effects include low blood pressure with standing, dizziness, feeling tired, and nausea. Serious side effects may include low blood pressure, liver problems, heart failure, and bronchospasm. Use appears safe in the latter part of pregnancy and it is not expected to cause problems during breastfeeding. It works by blocking the activation of β-receptors and α-receptors.Labetalol was patented in 1966 and came into medical use in 1977. It is available as a generic medication. In 2019, it was the 198th most commonly prescribed medication in the United States, with more than 2 million prescriptions. Medical uses
Labetalol is effective in the management of hypertensive emergencies, postoperative hypertension, pheochromocytoma-associated hypertension, and rebound hypertension from beta blocker withdrawal.It has a particular indication in the treatment of pregnancy-induced hypertension which is commonly associated with pre-eclampsia.It is also used as an alternative in the treatment of severe hypertension. Special populations
Pregnancy: studies in lab animals showed no harm to the baby. However, a comparable well-controlled study has not been performed in pregnant women.Nursing: breast milk has been shown to contain small amounts of labetalol (0.004% original dose).