Is Your Medicine Making You Fat?

If you're gaining weight for no reason or having trouble losing it, check the contents of your medicine cabinet. Experts don't fully know why some drugs pack on pounds, says Louis Aronne, MD, a weight-loss expert at NewYork-Presbyterian/Weill Cornell Medical Center, but your doctor may be able to switch you to a different class or lower dose of a drug. Here, some common weight-gain-causing meds and their smart swaps.

Drugs for: Depression
Could Cause Weight Gain: SSRIs such as paroxetine (Paxil, Pexeva), citalopram (Celexa)
Skinny Alternative: Bupropion (Wellbutrin, Aplenzin)
Our Expert Says: Some researchers believe SSRI-style drugs increase appetite. Antidepressants that affect dopamine, such as bupropion, may actually reduce hunger.

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Drugs for: Allergies
Could Cause Weight Gain: The antihistamine diphenhydramine (Benadryl, Alka-Seltzer Plus Allergy)
Skinny Alternative: Antihistamines loratadine (Claritin), cetirizine (Zytrec)
Our Expert Says: The alternatives contain different, less potent active chemicals, decreasing the chances that the drugs will boost appetite.

Drugs for: Insomnia
Could Cause Weight Gain: Diphenhydramine (in over-thecounter brands Sominex, Unisom, Nytol)
Skinny Alternative: Zolpidem (in prescription Ambien).
Our Expert Says: Occasionally taking an over-the-counter sleep aid shouldn't cause weight gain; for everynight help, consider switching to prescription.

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Drugs for: Hormonal birth control
Could cause weight gain: High-dose progesterone formulations, such as medroxyprogesterone (Provera, Depo-Provera)
Skinny alternative: Low-dose progesterone hormonal birth control formulations
Our expert says: Progestin hormones are so effective at causing weight gain that they're often prescribed for that purpose in cancer and AIDS patients. One study found that women gained an average of six pounds during the first year on these medications.

Drugs for: Asthma, allergies, inflammation
Could cause weight gain: Oral corticosteroids, including prednisone
Skinny alternative: Inhaled corticosteroids
Our expert says: Taking corticosteroids orally affects the entire body, which is why pills are more likely to cause weight gain than the same medication inhaled straight into the lungs.

Drugs for: High blood pressure, coronary artery disease
Could Cause Weight Gain: Powerful beta-blockers such as metoprolol (Lopressor), atenolol (Tenormin)
Skinny Alternative: Mixed alphaand betablockers such as carvedilol (Coreg)
Our Expert Says: With the single-effect beta-blockers, it can be harder to lose weight, possibly because they reduce metabolic rate.

By Regina Nuzzo

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