There is NO dumb question. Some 'uppities' act that way because your question happened to be one they knew! Ha!
Have to be REAL careful of the spelling because there are knock-offs galore: 1. Phentramin is an herbal supplement like Hoodia. It works for some but not others.
2. Phentramin-D is sold by the same company, and is available right here. It has ingredients that work chemically inside the brain to slow down your appetite. It contains caffeine and other ingredients listed It works works well for at least half the people who try it--MY GUESS! (they offered a guarantee at one time, if you purchased 3 months at a time. check that out)
3. phentermine works in the brain and addressed the satisfaction area of the brain and with SSRI's. You have seen that in descriptions of anti-depressants, and it has to be carefully administered to stay safe~It works for most but not all.
I a on the way to the grocery, but wanted to answer~