What Is Phendimetrazine?

Phendimetrazine is a prescription-only medication used for weight loss. It belongs to the class of drugs known as sympathomimetic amines, which are CNS stimulants similar to amphetamines. Although phendimetrazine is only FDA approved for short-term use (a few weeks), some doctors prescribe it for much longer periods of time, especially if a patient needs to lose a great deal of weight.

Function

• Phendimetrazine works primarily by decreasing appetite, but it may also increase metabolism. Some patients who take this medication report that it gives them more energy, which makes it easier to exercise regularly. Phendimetrazine comes in both sustained-release and immediate-release formulations. Sustained-release phendimetrazine is taken once daily and is particularly useful for people who tend to snack throughout the day. The immediate-release form of the drug is taken shortly before meals and is more helpful for those tend to eat too much at regular mealtimes.

Effects

• Like any prescription medication, phendimetrazine is associated with some side effects. The most common side effects associated with phendimetrazine are anxiety, insomnia, headache, dry mouth, restlessness, and changes in bowel habits. These side effects usually don't indicate a serious problem with the medication. However, if you experience irregular heartbeat, blurred vision, chest pain, confusion, hallucinations or abnormal behavior, seek medical attention immediately.

Considerations

• You should not take phendimetrazine if you have heart disease, glaucoma, uncontrolled high blood pressure, or have a history of drug abuse or addiction. Phendimetrazine interacts with MAOIs (monoamine oxidase inhibitors); if you take an MAOI, you must wait at least 14 days after your last dose before taking phendimetrazine. Talk to your doctor about any medical or psychiatric conditions you have before taking phendimetrazine; this drug may cause some conditions to become worse, or may require you to change the dosage of certain medications.

Warning

• Phendimetrazine is a scheduled substance, which means that it can be habit-forming. You should not increase your dose of this medication without your doctor's approval. You must stop taking this medication gradually, especially if you have taken it for a long time, to avoid symptoms of physical withdrawal. Phendimetrazine is considered a drug of abuse, and giving or selling this medication to another person is a felony.

Significance

• Phendimetrazine is an aid to weight loss; it does not replace the need for diet and exercise. This medication can make it easier to avoid overeating and to establish new dietary habits, but it will not cause you to lose weight if you do not limit your intake. In most cases, phendimetrazine is used to help people who have difficulty sticking to a program of diet and exercise. The drug is usually withdrawn after a few weeks, once new habits have been established.