A prescription only appetite suppressant, Phenteramine is often prescribed for obese patients at risk of heart disease. Although it has been registered since 1959, it is only recently that it has become more widely used for weight loss.
Phentermine is an appetite suppressant in the amphetamine and phenethylamine class, which appears to work by acting on the centres in the brain that control appetite - as a result, you feel less hungry. It is also a stimulant, so it will stimulate your nervous system, causing a rise in both blood pressure and heart rate.
Phentermine is prescription only, usually prescribed for the short-term treatment of extremely obese individuals with risk factors for heart disease. To be effective it must be combined with an appropriate diet and exercise plan.
Doctors consider this to be appropriate for no more than 12 weeks at a time, believing that it loses its effectiveness as an appetite suppressant as the body adjusts to it. However, there is some research that suggests that it is still effective for up to 36 weeks.
As you might expect with a drug this powerful, it should never be combined with other weight loss medications, and as it is a stimulant, it is recommended that you take it early in the day (before or after breakfast) to reduce the risk of insomnia.