Similarly, the acronym "TMA", which is frequently used for tetramethylammonium in the pharmacological literature, may also refer to the investigational drug 3,4,5-trimethoxyamphetamine, which, being a close structural analog of mescaline, has been the subject of numerous publications.

TMA has been detected in or isolated from a number of marine organisms, mostly amongst the Cnidaria and Mollusca, notably in some species of Neptunea (commonly called whelks) that are eaten by humans.

[4] TMA also occurs within the crystal structure Tsaregorodtsevite, a rare Sodalite group mineral with the formula N(CH3)4AlSi5O12 found on Gora Yaruta Mountain, Khanty-Mansi Autonomous Okrug, Russia.

[7] In the TMA cation, the methyl groups are tetrahedrally arranged around the central N atom, as is evident from X-ray crystallographic studies of various of its salts.

[2] Thus, the effects of TMA on nicotinic and muscarinic ACh receptors first stimulate, then block neurotransmission in sympathetic and parasympathetic ganglia, with depolarization.

[20] The human toxicology of TMA (under the name "tetramine") has been studied primarily in the context of accidental poisoning after ingestion of Neptunea species.

[2] Symptoms include the following: nausea, vomiting, headache, vertigo/dizziness, impaired vision/temporary blindness, diplopia, photophobia, lack of balance, feeling of intoxication and urticaria.

[4] Although many of these symptoms can be accounted for on the basis of impairment of neurotransmission in the autonomic nervous system, there also seem to be distinct indications of central affects.

[2] In animal studies, parenteral administration of TMA-containing extracts from Neptunea to mice, cats and fish mainly show effects involving skeletal muscles: there are muscular fasciculations, convulsions, loss of balance, motor paralysis and ultimately cessation of respiration.