(not presented as medical advice, or legal advice, or condoning illegal activity or recreational drug use in any way)
Interesting that Ecstasy is separated from other amphetamines on that chart. I guess I get why they do it, given the culture around MDMA, but it is a bit odd, technically speaking.
No, it's really not odd, technically speaking. They have completely different mechanisms of action in your body targeting totally different receptors, have totally distinct subjective effects (one's a straightforward CNS stimulant and the other has unique hallucinogenic and empathic properties), and amphetamines are not neurotoxic at therapeutic doses while MDMA directly damages serotonin receptors. They also have different abuse potential: while amphetamines are not neurotoxic at prescription doses and are safely prescribed to millions of ADHD kids, they can be readily abused at much higher recreational doses to get high and, though tolerance does build rapidly, can still be abused daily in similar fashion to meth abuse. On the other hand, while MDMA is directly neurotoxic, since it does not hit dopamine (read: addiction factor) substantially and requires a very long recovery interval in order to recover the serotonin receptors that all go supernova at once when taken, it's not a high risk for compulsive use/dependence since there's minimal physical craving and, being able to evaluate rationally in absence of a physical compulsion, you're just burning out your serotonin receptors all over again (or worse) but without feeling good from it if you don't wait a long time between uses. So it's a strange character in that it's directly harmful but has some built-in deterrents to abuse that can mitigate risk factors.*
Anyway, while they belong to the same chemical family, amphetamines and MDMA are not in the same class of drug for the aforementioned reasons and others. Radically different. If they're siblings then they're Cersei and Tyrion. Chemistry is a little more complicated than "it has methamphetamine right there in the name therefore _____." Laid out very thoroughly right on Wiki:
https://en.wikipedia.org/wiki/MDMA
https://en.wikipedia.org/wiki/Amphetamine
*However, it should absolutely be noted that MDMA is a street drug, and can and often does potentially include all sorts of harmful unknown adulterants or even outright substitutions with MDA, speed, meth, research chems, etc., so, much like with cocaine, users rarely know what they're actually putting into their body. For example, apparently cocaine in the United States has been increasingly adulterated with
levamisole to the point where it's found in almost 100% of what's currently circulating. It's there as a cheap cutting agent that can amplify the high, but is a medication intended to be used to treat parasitic infection -- yeah -- and can cause necrosis and outbreaks of papules all over your body or kill you outright. Not really what you want to be railing to party hard.
Point being, that's something no one should overlook when making personal decisions about recreational substance use: do you actually know what you're putting in your body? Some dangerous adulterants won't show up through typical reagent testing kits, or necessarily get removed by any "washing" procedures intended to remove adulterants either, so you need to factor in the very real risk of whatever random poisonous shit might be in there on top of the acknowledged risks of what you assume you're taking. I think someone earlier in the thread mentioned that over in Canada people are dropping dead now from coke being laced with fucking fentanyl, jesus christ, which Canadian drug dealers seem to have a real hard-on for,
as fentanyl is reportedly killing at least three people at day by inadvertent OD in British Columbia alone (typically sold as heroin or prescription opoid pills) and very easily a "poof, you're dead" outcome on the spot if there's just a tiny bit too much in there; too potent to measure accurately or safely outside of a medical setting, but too appealingly cheap to not be increasingly widespread as an undisclosed proxy for more expensive opioids in demand from the giant opioid epidemic in progress, so truckloads of people are dying at random right now.
It happened to
*Prince*, even. Reportedly he thought he was taking vicodin that was actually a street pressed fentanyl substitution that randomly had a lethal dose of fent in there. Tragic outcomes from random adulterants or cost-cutting substitutions can absolutely happen to anyone. Stay safe and be mindful of the full extent of the risk factors.