Since we don't allow tags describing a position, shouldn't we make the [alt-medicines] tag a synonyms of the [medicine] tag? Claims about alternative medicine can be verified by the same experts that can verify claims medicine. It's the same pool of expert; it's just that one of the two tends to have a lot more false claims.
Anti-vaccination is not a shot you can take instead of a regular vaccine. Alt med is not an opinion.
The pool of expertise may have a certain overlap, but not necessarily; more importantly, there isn't obviously an overlap in the pool of interest.
In medicine, your ideal respondent might be a doctor. If you ask "Propranolol against hypertension, is this a hoax?" a doctor might say, "Propranolol is a β-blocker, it blocks the action of epinephrine and norepinephrine, which will soothe hypertension and also tremor. Notably, Kim Jong Su from North Korea was a pistol shooter who won the Olympic Games in 2008, but was later disqualified for the use of propranolol. Incidentally, I'm not really a doctor and all of this info is from Wikipedia."
If you're talking about alt-medicine you might be asking something like "Can dilution really make a substance more potent?", to which our hypothetical doctor might only be able to say "I don't know. I've only studied real medicines. I really can't be bothered with all that homeopathy jazz."
Sure, alternative medicine is only medicine that hasn't been proven to work, but in our field, that's a pretty important distinction. Sure, there's an overlap of expertise, but hey, we're all skeptics here. There's an overlap of expertise between ufos and vaccines as well.
I think the important thing here is that the two tags will probably feature very different kinds of questions. The obvious problem, of course, being that when your question is "does X work?", you wouldn't know which of the two tags to use. I'd recommend going for alt med in those circumstances, since I believe that "does X work" will be the kind of question we'll mainly be seeing in that tag anyway.