I have a lot of thoughts on this. I recommend looking into Dr. Gabor Mate, out of Vancouver. He's an addiction specialist, trained MD. Works with a lot of drug addiction. He's been taking patients to the Amazon (Peru, I'm fairly certain), to go through an Aya treatment regiment basically. I think it's two weeks in duration and you actually drink the brew a couple times a week. You can contact him on his website, he's pretty good with responding. He's had really good success with it, and there are quite a few videos on youtube with him discussing it.
From what I've read, I would be hesitant with any place in a destination-type of location, such as Costa Rica. This, in my opinion, should be done in the most real environment as possible, such as the deep Amazonian rainforest with real Shamans. All of which, Dr. Mate talks about.
In regards to Costa Rica and these destination spots. There are a ton of stories out there, of Americans going down there for this and getting... screwed over to say the least. Amber Lyon explains an instance where she was touched/assaulted while at a spot in Mexico I think. So the more "western-ized" it is, the worse of an idea it is.
I'm really attracted to the idea of psychedelics to heal mental disorders and the evidence is becoming more and more apparent IMO. From psilocybin mushrooms for end-of-life palliative/terminal care, to MDMA-assisted psychotherapy for PTSD, and Ayahuascha and Ibogaine for opiate addition. If you want more information, check out
Research for up-to-date info on all of these topics