The U.S. Food and Drug Administration (FDA) approved a new weight loss pill on Wednesday. The drug called Contrave becomes the third prescription weight loss drug in the United States since 2012.

Contrave is formulated by combining an antidepressant drug (bupropion) and an anti-addiction drug (naltrexone). The bupropion lessens the appetite while naltrexone blocks the brain from cravings. Other existing weight loss drugs are Qsymia (phentermine and topiramate) and Belviq (lorcaserin).

The new weight loss pill can be taken daily by both overweight and obese people with increased risks of heart attack, stroke, high blood pressure and cholesterol, and type 2 diabetes. The FDA restricts pregnant women or those trying to get pregnant, those with seizure disorder, and eating disorders. Doctors suggest that it should be combined with diet and exercise.

"If you try to use it in isolation, that patient is not going to have success," said Bipan Chand, MD, director of the Loyola University Medical Center's Center for Metabolic Surgery and Bariatric Care, to WebMD News.

Researchers claimed that Contrave can effectively reduce weight by an average of 5 to 10 percent in 6 months. The study involved more than 4,500 participants who were grouped to take Contrave along with a weight-management program and another group who had placebo with the same program. Those who took the weight loss pill lost an average of 25 pounds while the placebo group lost an average of 17 pounds.

The FDA recommended at least 12 weeks of consumption to determine weight loss and advised patients to stop using the drug if they do not lose at least five percent of their starting weight. Health experts also warned that Contrave might increase one's risk to suicidal thoughts because of its antidepressant content, Healthday News reported.

Takeda Pharmaceuticals, Contrave maker, is still conducting studies to identify its heart attack and stroke risks. The company also plans to extend it to those with liver or kidney problems, as well as children use.

There is no official price released yet but experts believe that it will not be far from the prices of the existing weight loss pills which are around $6 to $7.