Plus, Agee said, some of her patients experienced side effects from phentermine, like palpitations and difficulty sleeping. She said she probably would not be prescribing Qsymia until it had been out long enough to ensure that it was effective and safe.
As for Anderson, he said the last diet medication he prescribed was Meridia, which was taken off the market in 2010 due to concerns over possible heart-related risks. Xenical, an FDA-approved weight loss medication still on the market today, works by stopping fat absorption -- but also causes diarrhea. Anderson said he abandoned it years ago.
"It is interesting and good that there are a couple new drugs available for weight loss," Anderson said. But he added that before prescribing either new medication, he said he'd like to see how effective they are and what the side effects will be.
For now, at least, primary care physicians will have time to make up their minds about these diet drugs. Neither Belviq nor Qsymia is currently available on the market.
Arena, which makes Belviq, cannot make the drug available until the Drug Enforcement Administration determines if it will be a scheduled substance. While Qsymia contains two medications that are already FDA-approved, it will need to be closely monitored by the Risk Evaluation and Mitigation Strategy required by the FDA.
Physicians will need to write the prescription on a specific form and fax or mail to pharmacies that have gone through a certification process to distribute Qsymia. Additionally, it is unclear what each medication will cost and how many insurers will cover their use.
While the future for the new potential blockbusters is uncertain, one thing is for sure -- the old advice to watch your diet and exercise remains the best way to lose weight and maximize health. It is worth noting that every patient in trials who lost weight on Belviq and Qsymia was also on an exercise and diet program.
"I understand the desire for a miracle pill, a silver bullet, to deal with the very difficult and stubborn problem of obesity -- but I don't think it's going to be that easy." Green said.
Anderson concurred. "It's still going to come down to exercise and diet as the best way to lose weight."