Weigh in on Weight loss Drugs

March 5, 2015

For many obese adults, diet and exercise are not enough to achieve durable weight loss. Three drugs are approved in the US as adjunctive therapy for obesity management. Weigh in with what you know with answers to these 3 questions.

According to the CDC, more than one-third (34.9%, or nearly 80 million) of US adults are obese. The now well-known obesity-related conditions include heart disease, stroke, type 2 diabetes mellitus, and certain cancers-some of the primary causes of preventable death.

Weight loss for the morbidly obese is not always possible with diet and exercise alone. Several medications are currently used as adjunctive treatment in the management of obesity. Some are sold over-the-counter, while others are prescription medications. Three drugs have demonstrated efficacy in controlled trials and have FDA approval for weight loss management: sibutramine, orilstat, and phentermine. Test your knowledge of these agents with these 3 questions. 

 

1. Which of these drugs was removed from the US market after an increase in cardiovascular event risk?

A. Sibutramine

B. Orlistat

C. Phentermine

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Answer: A. Sibutramine

Sibutramine is an anorexiant, which acts as a serotonin and norepinephrine reuptake inhibitor. Based on the results of a randomized controlled study published in The New England Journal ofMedicine in 2010, sibutramine was removed from the market in the United States and several other countries. In this large study, more than 10,000 overweight and obese subjects older than 55 with preexisting cardiovascular disease and cardiac risk factors (eg, diabetes) were randomized to receive sibutramine or placebo for 6 weeks. The primary outcomes were myocardial infarction, stroke, and death. Patients randomized to sibutramine had a small but significant increase in a primary outcome event. As a consequence, the FDA removed sibutramine from the market.

 

2. Which of the 3 agents is a lipase inhibitor?

A. Sibutramine

B. Orlistat

C. Phentermine

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Answer: B. Orlistat

Orlistat is a lipase inhibitor commonly used in weight loss management. It is available over the counter (Alli) and as a prescription (Xenecal), which is a higher dosage of the medicine. In controlled studies, orlistat led to a significant reduction in weight and waist circumference. Because it is a lipase inhibitor, it causes intestinal malabsorption, and its adverse effects include loose stools and fecal seepage.

 

3. Which of the 3 medications is/are considered pregnancy category X?

A. Sibutramine

B. Orlistat

C. Phentermine

D. All of them

E. None of them

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Answer: D. All of them

All weight loss medicines, including sibutramine, orlistat, and phentermine, are absolutely contraindicated during pregnancy.