Mescaline (3,4,5-Trimethoxyphenethylamin) belongs to the chemical class of beta-phenethylamines, and thus in one group with amphetamine, methamphetamine, MDMA, 2C-B and relatives.In the ethnopharmacological literature Mescaline is accounted to the Lophophora alkaloids.
The molecule differs markedly to the tryptamine entheogens, such as LSD-25, DMT, psilocybin, mescaline, etc. The way it acts is related to these substances though. It acts similarly visionary and psychedelic, but rather on an emotional-entheogenic level.
Mescaline was the first plant drug that had been tested by a pharmacologist self-experimentation. At the end of the 19th Century, Arthur Heffter from Leipzig rsp Berlin sampled a dose of 150 milligrams of mescaline hydrochloride. Since then, the bio assay, a self experimental test of a substance, is called "Heffter technique". Mescaline also was the first entheogen, that had been tested in the context of psychiatric therapy. At that time it was believed to be able to imitate the effects of the substance, a model psychosis to understand the consciousness of "mentally ill". Meanwhile, the science knows that psychosis and psychedelic experiences have no common denominator.
Besides, in some mescaline cacti are also, among the various secondary alkaloids, Mescaline-Citrimid for example, N-Acetylmescalin, N-and N-Methylmescalin Formylmescalin present. However, these are not directly relevant as psychedelics.