What Is the Difference Between Adipex and Phentermine?

Adipex-P is a particular brand name for a prescription drug which assists in weight loss, whose generic name is phentermine hydrochloride, commonly called phentermine. Adipex is the most popular brand of phentermine in the United States. Other brands, Ionamin and Duromine, are available as well, and phentermine can also be purchased generically.

Identification

• Phentermine hydrochloride is a stimulant and appetite suppressant which is similar to an amphetamine in effects. It prevents hunger signals from reaching the brain, and provides extra energy. Doctors prescribe it for people who are obese and who also have a related condition, such as high blood pressure, high cholesterol, or diabetes, which is increasing the person's risk of serious medical problems. Phentermine is to be used in combination with a diet and exercise program.

Types

• Manufactured and distributed by Gate Pharmaceuticals since 1990, Adipex-P is available in tablets and capsules. The other two brands of phentermine contain resin to create a slow-release form of the drug. Ionamin is made by Celltech Pharmaceuticals, Inc., while Duromine is manufactured by iNova Pharmaceuticals, and is most commonly used in Australia and New Zealand.

Features

• People can purchase generic phentermine by prescription as well. The active ingredients are chemically identical to those in Adipex, Ionamin, and Duromine, as are the dosage recommendations, safety, strength, quality, and intended usage. There may be different inactive ingredients. Generic phentermine is manufactured by Sandoz.

Significance

• Phentermine is much less expensive and more commonly-prescribed than Meridia or Xenical, the two other major diet drugs approved by the Food and Drug Administration. Phentermine accounts for about half of the appetite suppressant prescriptions in the U.S.

Warning

• The drug can cause rapid heartbeat and also is addictive if used for a lengthy time frame. Physicians only prescribe phentermine for short-term use, typically three to six weeks, to give the overweight person a good start at significant weight loss. Side effects include anxiety, irritability, restlessness, headache, and insomnia. It can cause negative reactions if the individual drinks alcohol. Phentermine can lower blood sugar, so people taking insulin or other blood sugar-lowering medications may need an adjustment of their dosage. People should not take generic phentermine or any brands of this drug if they have arteriosclerosis, glaucoma, heart disease, hyperthyroidism, an allergy to stimulants, or a history of alcohol or drug abuse. Phentermine also interacts with several other drugs, so it is important for people to tell their physicians about any other medications they are currently taking.