Preventive Medicine Column

Dr. David L. Katz

The nearly unanimous recommendation of a 22-member FDA expert panel to rescind a prior decision and approve the weight loss drug Qnexa says something about the FDA; something about Qnexa; something about obesity; something about those suffering from obesity; and something, most of all- something rather profound and quite ominous- about our society.

About the FDA: The FDA is constantly weighing risks and benefits.  Nothing in medicine, and little in life, is entirely free of risk. Effective chemotherapy for acute leukemia can be quite toxic- but less so than the leukemia itself.  An intra-aortic balloon pump is no walk in the park, but it beats cardiogenic shock.

There is, at present, only one FDA approved drug for weight loss, and it isn’t very good.  Other weight loss drugs that have been approved at some point no longer are. Qnexa did not have to be very good or very safe to produce 20 thumbs up.  It just had to be better than… nothing.

About Qnexa: The drug, in fact, isn’t very good.  True, it does produce a weight loss of roughly 10% of body weight over a year or two in clinical trials, and does outperform placebo- but so does every weight loss drug ever tested.

Qnexa is a combination of two drugs, phentermine and topiramate.  Phentermine is an amphetamine-like stimulant, and very unlikely to be safe or suitable for long-term use.  Among its common side effects is an elevation of blood pressure- one of the complications of obesity itself.

Topiramate is an anti-seizure drug.  It can, and often does, cause fatigue, brain fog, and nausea.  It is generally a bit difficult to get patients with epilepsy to keep taking such drugs because they often don’t feel very well on them.  But the risk of a grand mal seizure is a very potent incentive.  It’s hard to imagine anyone remaining on such a drug to keep off weight they have lost- and history indicates clearly that if and when the drug is stopped, the lost weight is likely to be refound.

The FDA panel recommended approval of QNEXA only because so many of us are so heavy, and the ranks of useful weight loss drugs are so thin- and desperate times call for desperate measures.

About obesity: We have developed potent treatments for cancer, heart disease, diabetes, infections, stroke, and almost every other condition we might add to the list.  Why can’t we come up with one for obesity?

I have an answer.  You would, I trust, expect that a fish with an infection could be treated with an antibiotic.  But I also trust you would not expect any medicine to fix the problem of a fish out of water.  There is nothing a pill could do, short of turning a fish into something other than a fish, that could fix the ‘out-of-water’ problem.  And obesity is just like that.

Just as it is normal for a fish to breathe in water and asphyxiate out of it, it is normal for humans to turn a surplus of calories into an energy reserve, namely, body fat. You can save the fish- just not with a pill.  Throw it back in the water.  More on that below.

About those with obesity: Many people with obesity are overwhelmed.  They cannot fix the problem with the resources at their disposal- and are desperate for any new option.  Even an option that combines an amphetamine with an epilepsy drug.  The victims of epidemic obesity need help they aren’t getting- and will accept it even in the form of a pill you couldn’t pay most people to take!

About our society: Very little about genes, metabolism, or human nature has changed in the past 5 decades.  We have epidemic childhood obesity now; we did not have it then.  The ambient level of ‘personal responsibility’ in 8-year-olds has not changed over that span.  A dramatic change in the epidemiology of obesity is directly related to profound changes in our environments, food supply, activity levels, and social norms. We have caused the obesity epidemic, by looking the other way as a staggering array of ‘advances’ made ever more calories ever more temptingly available, and made physical activity ever more elusive.

The root cause and cure of all but rare cases of obesity resides with how we use our feet and forks.  Pharmacotherapy is no substitute.

There is, indeed, a role for pharmacotherapy for obesity- as there is a role for surgery.  But it should be a small role. I protest is any indulgence in the idea that this is a meaningful solution to the problem of epidemic obesity.  I protest the attention and resources that get diverted from making the modern environment more salutary, more conducive to healthful use of feet and forks.  As a society, we should be doing all we can- and we are not!- to make sure very few of us ever need the options of surgery or drugs.

FDA approval of Qnexa will represent a rather desperate measure at a desperate time for desperate individuals of a desperate society.  So be it.  But our desperate need to address this problem decisively is long overdue, and should be the mother of far better invention than this.




Dr. David L. Katz;