Obephen is a prescription using the active ingredient Phentermine. It is similar to an amphetamine, stimulating the central nervous system to suppress appetite. It is often used coupled with diet and exercise, but only used for a few weeks while diet and exercise should continue, essentially to jump start your diet plan. It is generally used for those who also suffer from risk factors such as high blood pressure, high cholesterol, and diabetes. Taking it with drugs such as Phen-Fen or Redux can cause a rare lung disorder known as pulmonary hypertension, so doctors should always be consulted on a regular basis with this drug. Side effects are common, and you should not take it in combination with certain prescriptions such as MAOI inhibitors. You should not take this drug within 14 hours of bedtime as it may cause insomnia. Should you find this dose of Phentermine inappropriate, unless there is some kind of reaction to Phentermine in general, you might want to try another brand of Phentermine.