Yah, I don't think its actually medicine but maybe a stress reducer conditioner. Second time for Ich in this tank.Glad to hear. My LFS has used it a several times with moderate success when deployed early. I have too much coral & rock & fish for a true fallow. Given that, I have used it too. It seems to help.
You might be well served to think of this as a management tool versus an eradication tool. That is how I look at it. Ich has returned a time or two. It takes a few fish. I slap on a big UV and dose Medic. Then everything clears. I have fish that have had ich 2-3 times in the last 14 years and are still kicking. Others just up and die at the first sign.
The first bout a few fish got it but the Purple Tang had it for over a month and finally cleared. None died. He got it this time but has cleared already. Management.