Sounds like a major game changer - thanks for pointing it out!
I did a minor bit of PubMed digging, looks like researchers have been chasing this for some while as dysfunction in the sodium channel NaV1.8 is why some people cannot feel acute or chronic pain. And apparently, there is/was an insecticide that blocks one of the NaV channels (the important ones for humans are 1.7, 1.8, and 1.9)