It seems that this topic died down a long time ago. I haven't seen a thread about KOR antagonists on this forum for many years...but I'm wondering if anyone in 2026 knows of a legitimate vendor or other source that offers a selective KOR (Kappa Opioid Receptor) antagonist?
Basically, I'm talking about either JDTic, Norbinaltorphimine (nor-BNI) or Aticaprant.
There have been lots of other KOR antagonists thrown around on this forum but most of these aren't what I'm looking for. For example Amentoflavone's action on KOR is weak and others (like Buprenorphine & Naltrexone) aren't selective for KOR and are actually much more active at the MOR, which is an undesirable effect for what I'm looking for.
However, if you know of another KOR antagonist (apart from the 3 I mentioned) that is selective and strong-acting... feel free to mention it.
I do know of pglchem as a source for nor-BNI. However, that's the only one I've found and I'd like to explore alternate options if they are ones. As of yet, I do not know of a vendor that offers JDTic or Aticaprant.
Feel free to send me a DM if you'd rather communicate that way.














