The term "empathogen" was coined in 1983 by Ralph Metzner to denote chemical agents inducing feelings of empathy.
"Entactogen" was coined by David E. Nichols as an alternative to "empathogen", attempting to avoid the potential for improper association of the latter with negative concepts related to the Greek root "pathos" (suffering); Nichols also thought the word was limiting, and did not cover other therapeutic uses for the drugs which go beyond instilling feelings of empathy. The word "entactogen" is derived from the roots "en" (Greek: within), "tactus" (Latin: touch) and "gen" (Greek: produce). Neither term is dominant in usage, and despite their difference in connotation are essentially interchangeable as they refer to precisely the same chemicals.
These drugs appear to produce a different spectrum of psychological effects from stimulants such as methamphetamine and amphetamine or from psychedelic drugs such as LSD or Psilocybin. As implied by the category names, users of entactogens say the drugs often produce feelings of empathy, love, and emotional closeness to others. However, there have been only very preliminary comparisons of these different drugs in humans in properly controlled laboratory studies.
If MDMA is taken as a representative entactogen, the pharmacological mechanisms of this class appear to resemble those of methamphetamine. Extracellular dopamine, serotonin, and norepinephrine are all increased by both MDMA and methamphetamine. However, entactogens other than MDMA have received relatively little scientific attention, making it difficult to draw conclusions about the mechanisms of entactogens in general. It is also unknown why entactogens might produce emotional effects that differ from stimulants.
References
- Nichols, D.E., Hoffman, A.J., Oberlender, R.A., Jacob P 3rd & Shulgin A.T. Derivatives of 1-(1,3-benzodioxol-5-yl)-2-butanamine: representatives of a novel therapeutic class 1986 J Med Chem 29 2009-15
- Nichols, D.E. Differences between the mechanism of action of MDMA, MBDB, and the classic hallucinogens. Identification of a new therapeutic class: entactogens 1986 J Psychoactive Drugs 18 305-13