The use of appetite suppressant drugs is rather popular because they seem to achieve very fast short term weight reductions. However the long-term results are usually poor, if no behavioural change takes place. Most appetite suppressant medication is very similar to amphetamines and there is a major risk of tolerance and misuse of these drugs. Avoid phentermine if you have a history of anxiety disorder, heart problems, high blood pressure, glaucoma, thyriod disorders and epilepsy. Any use of appetite suppressant medication during pregnancy or nursing should be avoided. There are alternative medicines or supplements that has the same weight reducing factors like Zantrex-3 and they are made from natural ingredients.