If I had a dime for every patient that ever asked me if "there was something I could take" to "help me lose weight," I'd certainly be well off. I must have heard that more than I'd care to remember. The answer to that question is rather complicated. There are a few medicines out there that have been FDA approved for weight loss, but they are few and have some intolerable side effects for most of us.
The oldest weight loss concoctions on the market are in the sympathomimetic family, such as methamphetamine, phentermine and others. These are highly controlled substances that "rev up" your metabolism- which is why they were commonly called "uppers." Some unpleasant side effects include dry mouth, rapid heart rate, insomnia, anxiety and high blood pressure. Do they work? They sure do - in the short term. They're only approved for use for up to 12 weeks as part of a weight loss program. Often, however, they are used for longer periods and users become dependent on them.
Moreover, tolerance develops to their appetite suppressing properties and it is difficult to come off them. Abuse can easily develop. Phentermine was commonly prescribed as a weight loss medication in a pill combination with fenfluramine - the popular "phen-fen." This medication was effective at helping lose weight, but it was later associated with heart valve defects and pulmonary hypertension and was taken off the market.
Some over the counter medications have been touted as weight loss pills. More often than not, they contain caffeine which acts as both an appetite suppressant as well as a mild diuretic which will help one lose "water weight." Of course, the issue with these is that the water weight easily returns once some salt and water are ingested and the appetite suppressant effects come with some unwanted side effects such as nervousness, tremulousness and headache.
There were a number of patients who I would see who would be participating in local "weight loss clinics." These venues were usually staffed with physicians who would prescribe a combination of phentermine as well as either furosemide (a rather potent diuretic) and/or hydrochlorothiazide (another potent diuretic). Again, the scheme of these clinics was to give the patient a "quick fix." The combination of the appetite suppressant effects of the phentermine along with the rapid water weight loss of the diuretic had the patients very excited that they were losing weight rapidly. The problems was, not only were there side effects of the phentermine as mentioned above, but the water weight loss, much like caffeine, was easily replaced once the user ingested salty foods and fluids. Moreover, continued use of diuretic pills without paying close attention to electrolyte balances in the blood (like sodium and potassium levels) can be very harmful to one's health as well as difficult on the kidneys.
Bottom line? As far as these drugs are concerned - they're a bust. The best one can hope for is a quick head start with weight loss that ultimately is not sustainable. Furthermore, these drugs can be downright dangerous if close responsible medical follow up is not obtained.
The news isn't all bad though. In the blogs to follow, I will run down a couple of FDA approved drugs that appear to be safer, can be used for longer periods, and help contribute to weight loss as part of a more comprehensive program that also includes sensible eating and lifestyle changes. Whether or not they are "magic pills," however, may be another story.