Phentermine is a prescription medication that is used as a short-term adjunct to a weight loss program, including diet and exercise, for individuals who are overweight or obese. It is classified as a sympathomimetic amine and works by suppressing appetite and increasing feelings of fullness.

Phentermine is thought to work by stimulating the release of certain chemicals in the brain that control appetite. It primarily acts as a central nervous system stimulant, similar to amphetamines, and can help reduce food cravings and increase metabolism.

It is important to note that phentermine should only be used under the supervision and prescription of a qualified healthcare professional. The medication is typically prescribed for a limited period, such as a few weeks or a few months, due to its potential for tolerance, dependence, and abuse.

Phentermine is not appropriate or safe for everyone. It is generally prescribed for individuals with a body mass index (BMI) of 30 or higher, or those with a BMI of 27 or higher with obesity-related health conditions, such as high blood pressure, diabetes, or high cholesterol.

Phentermine may have side effects, including increased heart rate, elevated blood pressure, insomnia, restlessness, dry mouth, constipation, and nervousness. It is not recommended for individuals with certain medical conditions, including heart disease, glaucoma, overactive thyroid, or a history of drug abuse.