It is very important to ensure that, there is a possibility of side effects even bearing in mind that this is not the same as amphetamine. Therefore, under every respect, you must go for prescription. The doctor will do this according to your weight and height. This means that if your height and weight calculation is high (over 30), the doctor may agree that a prescription will work on you on your diet and exercise programs. This means that you will be on chemotherapy for weeks or even months then back to your normal weight loss programs. The doctor may in some cases prescribe a special medication for you if you have atherosclerosis – a history of Alcohol or drug addiction, high blood pressure, allergies to such medication diabetes or even one is on anti-depressants (like MAO inhibitors). This one depends on if you are capable to read the handwriting of you doctor. The prescription may be clear that it is not phentermine without prescription pills because phentermine is a name of the chemical compounds that are found in different products. Phentercot, Adipex, teramine, Fastin and pro-fast are brands that have the same active ingredients of phentermine. A special resin is evident in Ionamin, a formula that provides a long life. Phentermine 37.5 is a generic version of phentermine but comes in a large dose. This one is a great if you need a larger dose of the drug.