Contraindications. In an earlier post, we discussed indications for the use of weight loss medications. It is important to understand the presence, or history, of certain medical conditions, the presence of drug allergies or intolerances and current medications may affect the appropriateness of a particular weight loss medication or even class of medications. The final decisions regarding the use of a medication and the which one is recommended will be between you and your health care provider.

Sympathomimetic amines (Phentermine, Phendimetrazine, Diethylpropion)

These medications have been around for many decades. All are available in generic form and are relatively inexpensive (<$50/month). Phentermine is the most commonly prescribed weight loss medication in the US. This class of medications works by directly suppressing appetite. Depending on the drug and dose, it works for six to twelve hours. Most patients eventually develop tolerance to sympathomimetic amines.

Qsymia (Phentermine + Topirimate)

This medication has been out for a couple of years, is not available in generic form and costs about $135 per month. The Phentermine component works as described above. The mechanism of action for Topirimate is unknown. Qsymia may help patients with obesity and binge eating disorder gain control of both problems. Qsymia produced more weight loss than any other weight loss medication in clinical trials (8%).

Saxenda (Liraglutide)

Liraglutide has been available in various formulations for several years. Saxenda is an expensive medication, about $1300 per month. Saxenda is an injectable medication with once-daily dosing usually in the morning. Saxenda works on a hormone (GLP-1) which helps us to feel satisfied with smaller portions of food. Saxenda is the only weight loss medication proven effective when initiated in patients who have already lost a substantial amount of weight.

There are other medications available for the treatment of obesity but are prescribed less commonly than the medications outlined above. Medications for weight loss are truly adjuncts to diet and exercise. If you want to lose weight, you must restrict your calorie intake. If you want to keep it off, you must embrace a habit of daily exercise. The whole process is more efficient if you embrace the need for a lifestyle change. In the end, like achieving most things of value, you have to work for it.