If the overweight conditions continue more serious health problems will develop like heart disease, diabetes, and stroke. This is where drugs like Phentermine have their greatest benefit. phentermine 37.5 Phentermine is an anoretic which means that it functions as an appetite suppressant by causing the release of chemicals in the brain that control hunger. Phentermine is not intended for long term use and those taking it should be careful of developing a psychological dependence.