A 34-year-old woman visits the office because she is unable to lose weight despite diet and exercise. She claims she gained a significant amount of weight after quitting smoking four years ago. In the previous year, the patient tried several commercial weight-loss diet programs without success. She hopes to lose at least 4.5 kg (10 lb) in the next few months before her wedding. The patient has no other medical conditions and is not on any medications. The blood pressure is 122/80 mm Hg, and the pulse rate is 78 beats per minute. The BMI is 33 kg/m2². Physical examination reveals an obese habitus but nothing else notable. Laboratory testing for secondary causes of weight gain is unrevealing. In addition to encouraging continued efforts at lifestyle change, the physician prescribes a short course of oral phentermine for weight loss. The weight loss induced by this medication is caused by which of the following mechanisms?

Question

Quizplus · Accepted Answer

Eductional Objective: Norepinephrine-releasing agents (e.g., phentermine) are sympathomimetic weight-loss medications used to treat obesity in the short term. They stimulate norepinephrine release while inhibiting reuptake. Subjective effects include an increased sense of satiety, which leads to less caloric intake. With these drugs, weight regain after cessation is common.

A 34-Year-Old Woman Visits the Office Because She Is Unable