(CNN) - The U.S. Food and Drug Administration is expected to approve a new prescription diet drug called Qnexa on Tuesday. The medication produced dramatic weight loss in clinical trials, but some are concerned over potential side effects, including increased heart rate, birth defects and other issues.
If approved, Qnexa (pronounced kyoo-NEX-uh) would become the second diet drug approved this year. The FDA approved a weight-loss pill called Belviq on June 27.
Patients in clinical trials experienced more dramatic weight loss with Qnexa than with Belviq. On Qnexa, patients went from an average 227 pounds to 204 pounds; on Belviq, the average weight dropped from 220 to 207.
But some consumer advocates worry the weight loss comes with a price. Some patients in the clinical trial suffered an increased heart rate and a condition called metabolic acidosis, which can lead to hyperventilation, fatigue, and anorexia.
This morning on "Starting Point," Elizabeth Cohen explains the Qnexa safety concerns.