WASHINGTON (CBSMiami/AP) — For the second time since June, the Food and Drug Administration has approved a new prescription diet drug.

It’s called Qsymia, formerly known as Qnexa. It’s for overweight or obese people who also have at least one weight-related condition such as high blood pressure, diabetes or high cholesterol.

Patients in clinical trials lost an average of 23 pounds.

Some consumer advocates are concerned about the drug’s side effects, which could include hyperventilation, fatigue, tingling of the hands and feet, dizziness, insomnia, constipation, and a change in taste sensation and dry mouth.

Pregnant women should not take Qsymia because it may harm the fetus, the FDA said. The FDA also doesn’t recommend the drug for patients with glaucoma and hyperthyroidism, or patients with recent heart disease or stroke, since the drug may also elevate heart rate.

Qsymia is an extended-release combination of two older drugs, phentermine and topiramate. Phentermine is an amphetamine approved for short-term weight loss and topiramate is prescribed to prevent seizures and migraines, and is supposed to make pill-takers feel fuller.

Phentermine was one-half of the popular Wyeth drug fenfluramine, or fen-phen, which was tied to heart valve damage and taken off the market in 1997, resulting in a $13 billion settlement over tens of thousands of lawsuits.

The drug is to be prescribed in combination with a reduced-calorie diet and exercise.

The drug is recommended for obese patients with a BMI (body mass index) over 27

Qsymia’s approval follows the FDA’s approval of another obesity pill, Belviq, which was the first weight-loss pill approved by the FDA in more than a decade.

Qsymia is expected to be available by the fourth quarter of this year. It’s not known how much the pills will cost.

According to government estimates, more than one-third of U.S. adults are obese.

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