Tetraethylammonium
Tetraethylammonium is an experimental drug with no approved indication or marketed formulation. The only marketed drug containing tetraethylammonium was a combination drug called Fosglutamina B6, but this drug has now been discontinued. As an experimental agent, tetraethylammonium is used in its salt forms such as tetraethylammonium chloride and tetraethylammonium bromide. Its mechanism of action is still being investigated, but it is known that tetraethylammonium blocks autonomic ganglia, calcium- and voltage- activated potassium channels, and nicotinic acetylcholine receptors. Because of its inhibitory actions at the autonomic ganglia, tetraethylammonium was thought to be a potential therapeutic vasodilator but serious toxic effects were found. The most common use of tetraethylammonium presently is as a pharmacological research agent that blocks selective potassium channels. Structurally, tetraethylammonium is positively charged due to its central quaternary ammonium.