Whatever you think of the health risks, all of these diet pills follow a basic pattern:
In the first week or month they work great. Depending on the pill, your appetite is down or you lose weight quickly without much effort. But your body will soon adjust! Your body will start working against you to compensate for the changes that just occurred.
Soon enough they stop working altogether or you need to exercise even more to fix your body's compensation. This also can affect your mind as you may feel elated on the pills or have extra energy that just crashes later.
Try to avoid these over the counter medications.
If you feel you need something, talk to your doctor. There are more mild and natural appetite suppressants like Potassium which can be prescribed as part of a diet program. This can be a good dieting extra because in many diets you don't get enough.
The right decision at the right time.