Adipex is a brand of phentermine. Many people get confused by this, let us explain a little more about Adipex:
Adipex is a brand name given to a diet pill that contains the chemical substance "phentermine". Phentermine is the active ingredient which is what makes Adipex work. A bit like "yeast" is the active ingredient that makes bread rise in Sara Lee bread. Adipex is also known by the name Adipex-P.