Remember when the term "designer drug" was used in the 1980s? One of the drugs included in that group was called 3-methylfentanyl, aka, mefentanyl. Although not widely used, it killed groups of people who tried it. Fast forward 4 decades and it's now one of the 30 fentanyl analogs that are responsible for the fentanyl crisis. And it's also one of the worst. What a difference a methyl group can make.
The DEA, which has been merciless to pain patients in its misdirected war on opioids, just stepped it up even further. Thanks to an Oregon Representative, we now have SORS (yet another way to restrict prescription painkillers) and SUPPORT, the law that created it. Just plain (and pain) awful.