There’s nothing unethical about self experimentation. There are many notable examples of it in the history of science. Most notable is probably Barry Marshall’s decision to self-dose with helicobacter pylori, in an effort to prove that the bacteria caused ulcers. They did, he treated himself with antibiotics, and he was later awarded a Nobel for the research. Werner Forssman also won a Nobel for work partially derived from self-applying a cardiac catheter.

I'm not sure what ethical considerations come up when testing a medical hypothesis by self-administration. Famously Barry Marshall overturned decades of medical doctrine when he ingested helicobacter pylori, and demonstrated its role in gastritis (and I think providing evidence for peptic ulcers).

That's the feeling I got, that they've tried it out on themselves, but (understandably) neglect to mention it. Which is a shame, because the self-censorship isn't helpful in regards of getting to the bottom of this.

But maybe I'm reading too much into it.

You need to learn about this guy then https://en.wikipedia.org/wiki/Alexander_Shulgin

Self-experimentation allows one to conduct science without the imprimatur of the IRB. IRBs, in the name of ethics, fashion themselves as the sole arbiter of what science may be done. Ergo, any loophole that circumvents their authority is prima facie "unethical".

It's probably not ethical. How repeatable it is is for an experiment to decide, if it was possible to arrange ethically.