Thought I'd check in here. I was on Phen/Fen when it was legal and had no problems. Signed a waiver and went happily from there. Of course, I gained it all back once I stopped taking it. Back then, my mentality was to get away with doing no work at all. Eat the same crap just smaller amounts of it.
I have since tried many over the counter pills with no success. Again, wanting them to do all the work.
Since being on Medifast, I tried Xenadrine because I was losing my oomph. Believe it or not, it made me hungrier! It might have been the upping of my metabolism - I don't know.
IF you decide to take any pills that are aimed at weight loss, I'd go to the doctor. Prescription diet pills still exist and if you take small enough amounts and stay monitored, I can't see why it wouldn't be safe. Everyone is different though.
There are pills that are mostly fiber instead of speed - don't know a thing about them.
Good luck!!
Kat