when is called phentermine, the other is called topirimate. effective together to produce weight loss. phentermine has been around for decades, and topirimate is also around. >> when you say very effective, what does that mean? is there a number? >> well, there have been a number of studies, and the most recent study lasted for a little over a year. and the person who takes the higher dose and sticks with the treatment may be expected to lose about 14% of body weight. so if you're 200 pounds, that would be about 28%. having said that, though, that's an average weight loss, and a third of the patients lost even more weight than that. and then there are some people who don't respond that well. >> look. i know we're a nation of fatty mcfat fats. i'm on jenny craig and ready to bite your arm at the moment. when i hear there's a drug we can possibly take, why all the controversy? >> i think weight loss drugs have had a very checkered past. you know, as you say, causing heart problems and lung problems. so, you know, we need to definitely proceed wi

it failed to win advisory committee approval in 2010 because one ingredient-- phentermine, an ingredientin the failed diet drug fen-phen-- was linked to heart problems. the other, topiramate, was linked to birth defects. dr. kenneth burman is on the panel that recommended approval to the f.d.a.>> the potential benefits of the medication seem at this time to trump the potential side effects but in truth only time will tell. >> reporter: the benefits of qnexa include up to 15% weight loss, lowering the risk of problems like diabetes and high blood pressure. the university of alabama's dr. tim garvey led clinical trials. >> i see the ravages, that obesity can exact on people. we don't have a medication right now like qnexa, a tool like this that we can use to help patients lose significant amounts of weight. i can tell you, my patients are looking for a medicine like this. >> reporter: the drug maker has agreed to continue to monitor patients for potential heart problems and to warn women taking the drug not to get pregnant. a final decision by the f.d.a. is expected in april. >> pelley: jo

>> reporter: she weighed more than 200 pounds when her doctor put her on two drugs, phentermine and an antiseizure and migraine medication. >> within the first year i lost over 50 pounds. >> reporter: the pill combining the two drugs is called qnexa. the fda advisors rejected the drug in 2010 concerned about side effects including heart problems and birth defects. but new findings eased their concerns. >> should everyone who is obese take qnexa? no. but many, many people will benefit. >> reporter: however, ucsf cardiologist dr. rita redburg is concerned many could be harmed. she says we need more long-term data on the risks and benefits. >> i don't have a good history of getting post marketing studies of getting data after the drug is approved and especially for a drug which clearly millions of people would consider taking, you know, even small rare adverse events are going could tomorrow out. >> reporter: currently there is only one fda-approved drug approved for weight loss, xenical. >> there are these two medication that work so well for me and i think it would be amazing for more p

>> she weighed more than 200 pounds when her doctor put her on a combination of drugs, phentermine. the new diet pill, qnexa combines both those drugs. lost 10% of their body mass. but the fda rejected this drug back in 2010 concerned about potential side effects, including heart problems and birth defects. the makers of qnexa showed encouraging findings. >> one of the outcomes of the studies that have been performed said all of the risk factors seem to improve. >> fda has not approved a new drug more than a decade ago. marion says people like her need more options. >> there are these two medications that work so well for me, you know, i think it would be amazing for more people to be able to have access to this medication. >> we're going to be watching when and if it becomes available. it isn't binding, but the agency usually does follow their advice, especially when a vote is like this. the fda is expected to make its final decision in april. >>> this is 9news now. >> how safe do you feel on public transit? the washington metropolitan transit authority has not done enough and they

it's a combination of two drugs, phentermine and topamax. doctors have been combining them off-label and helping people, people who are morbidally obese, dropping 10% of their body weight. for some people that's enough to get them out of heart disease problems and diabetes. but it doesn't come as a free ride. there are heart implications. there are sfeide effects. and there's been no medication for next ten years. it is the holy grail in the pharmaceutical industry because we're getting fatter and everybody wants the magic pill. >> there's -- did you think there's not enough urgency -- >> everybody is looking for the magic fix. because we've gotten so much out of control. you know, it can be a pill, it can be surgery. it can be a fad diet. but the long-term effects is really about changing your lifestyle. >> keep your mouth shut. we're a society that doesn't want to pay any consequences. and the down side of having a pill for everything it allows people for lack of a better word, misbehave. there are a lot of people obviously that have thyro

it's a combination of two appetite suppressants including one called phentermine. it is considered safe but was part of notorious fen-phen taken off the market years ago after it was linked to heart valve problems. the fda advisers scrutinized the latest safety data on quenexa not once but twice originally voting to reject the drug in 2010. but many doctors say they have been using the medications that comprise quenexa off label in patients for more than a decade safely and successfully. >> when we use these types of treatments, people are able to stick with a lo-calorie diet program. they're more enthusiastic about exercising because they see success. >> reporter: the potential for further success is significant. more than two-thirds of americans are considered overweight or obese. erica edwards, nbc news. >>> now the food and drug administration is expected to make a final decision on the drug later this spring. >>> speaking of spring, spring fever is now upon us. the pollen, even the pollen can't wait to get out. >> it's dancing. >> doug is in fairfax county ton

one is phentermine. it's like a still mulant.er one is used to treat migraine headaches and seizures. it can give people a filling of fullness. it's a combination of both these drugs. as you indicated, it's been studied for some time. they said the safety studies were inadequate a couple of years ago but found that it was effective in certain segments of the population. people who had really high body mass index or obese, they were able to lose weight, about 10% of their body weight while taking this pill. >> this has got a lot of people talking about this, the possibility of this diet pill and losing weight. the fda rejected it before. what were some of the concerns previously? >> well, with a lot of diet pills -- and i think you know me well enough and i advocate diet and fitness. but we have a real obesity problem in this country and a lot of the things that we advocate doesn't work. it increases the enthusiasm. but it's counterbalanced by heart rate went up, psychiatric issues with this pill and also birth defects. imagine so