Is Your Medicine Cabinet Making You Fat?
Experts explain how certain prescription drugs can cause unwanted weight gain.
Alternatives That Don't Cause Weight Gain
Aronne says he warns against putting too much stock in a list of specific drugs that cause weight gain.
"What you need to know," he tells WebMD, "is that certain types of drugs can cause weight gain." But in almost every case, the doctor will be able to switch you to another medication that has the same desirable effects but which will not cause weight gain and may even help you to shed a few pounds, he says.
For example, while some drugs used to treat depression and other mood disorders can cause weight gain, the antidepressants Wellbutrin and Prozac tend to help people lose weight, says Aronne, who is also clinical professor of medicine at Weill-Cornell Medical College in New York City.
Ditto for diabetes medications. "Yes, some can induce weight gain, but Glucophage and Precose are both weight-neutral, while two newer drugs -- Byetta and Symlin -- can actually help you lose weight," he says.
As for medications used to treat seizure disorders and headaches, Aronne says that Zonegran and Topamax are good alternatives that are both associated with weight loss.
Aronne recalls the case of one 190-pound woman being treated for migraine headaches who came to his obesity clinic. His team tried a variety of measures, even a liquid diet, to help her shed the unhealthy excess weight, but she stabilized after losing only 10 pounds.
"Then we switched her to a different medication, Topamax, for her migraines," he recalls. "She lost 50 pounds and has stabilized at a healthy 133 pounds. I can offer dozens of more examples just like this."
When to Suspect Drugs Are to Blame for Weight Gain
Fernstrom says you should suspect your medicine cabinet is at the root of your problem if you gain five or more pounds in a month without overeating or exercising less.
"You have to look at your lifestyle carefully and then if you still can't explain those extra pounds, you should begin to suspect it's your medication, particularly if you recently started a new medication," she says.
At that point, you can check the package insert or ask your pharmacist if weight gain is among the side effects of your medication. But the insert may not be as helpful as you might think, often simply listing weight gain as a "frequent" side effect, along with a dozen or so other side effects that may include weight loss, says George Blackburn, MD, PhD, an obesity expert at Harvard Medical School.
"You really need to see a doctor," and not just rely on lists or package inserts, he tells WebMD.