Alternative medicine is afaik medicine that is not part of traditional academic medical education. This is at least who it would be defined in German. Not sure if it is the same in English. We actually have specific words for that: “Schulmedizin” means academicly accepted medicine.

So yes, it would also be medicine. But different than e.g. ibuprofen or radiotherapy.

But tbh, I cannot think of an example. So maybe there is none? Don’t know, I am personally not that interested in alternative medicine.