Are you gaining weight and you don’t know why? The answer could be lying in your medicine cabinet! Weight gain is side effect of many medications, even some that are critical lifesaving drugs. Here is list of eight common medications that could be contributing to unexplainable weight gain and what you could do about it.
- Diabetes drugs
Diabetes drugs that may cause weight gain include:
- Injectable insulin: Insulin is a hormone that works by helping the body’s cells absorb glucose. But insulin causes a spike in weight when the cells absorb too much glucose, and the body converts it into fat. Not everyone with type 2 diabetes takes insulin, but insulin isn’t the only type 2 treatment that carries this side effect.
- Sulfonylureas (such as glyburide, glipizide and glimepiride) reduce blood sugar levels by 20 percent, but they can also cause a weight gain of 4 to 5 pounds on average, according to a study published in Archives of Medical Science. That’s because they stimulate beta cells in the pancreas to release insulin.
What to do: These medications are often commonplace in diabetes management, but there are newer medications that promote weight loss and should be considered. Most of not all of the common weight loss drugs in the GLP-1 class started their lives as diabetes medications. Two of the common drugs in this class are semaglutide (Ozempic) and tirzepatide (Mounjaro). Metformin is also linked to modest weight loss.
- Antidepressants
If you’ve been on an antidepressant for a while and you’ve put on weight, it could be a sign of improved mood if weight loss was a symptom of your depression. Significant weight gain, on the other hand, is likely a side effect of the medication, especially if you’re taking an SSRI (selective serotonin uptake inhibitor), the most commonly prescribed class of antidepressants.
Antidepressants that may cause weight gain include:
- Paroxetine (Paxil)
- Sertraline (Zoloft)
- Citalopram (Celexa)
What to do: With many second-generation antidepressants, there is often no weight gain; some, such as bupropion (Wellbutrin), may even result in weight loss. “Weight neutral” options, which don’t make you gain or lose weight, include fluoxetine (Prozac) and escitalopram (Lexapro). Serotonin-norepinephrine reuptake inhibitors (SNRIs) such as duloxetine (Cymbalta), desvenlafaxine (Pristiq) and venlafaxine (Effexor) are often considered weight neutral. Those that lean toward weight loss, like fluvoxamine (Luvox), may be used as an alternative to citalopram.
- Beta-blockers
Beta-blockers work by slowing the heart rate, the heart’s workload and its output of blood, all of which lowers blood pressure. That’s why they’re often prescribed to treat hypertension, angina and irregular heartbeat. If you’re on a beta-blocker, no one has to tell you the side effects include fatigue, insomnia and a slow heartbeat. All of those can add up to a less physically active lifestyle, which — no surprise — may result in extra weight.
What to do: If you’re on a beta-blocker and weight gain is an issue, talk to your doctor about possible alternatives, such as carvedilol (Coreg), a nonspecific beta-blocker; angiotensin converting enzyme (ACE) inhibitors; angiotensin receptor blockers (ARBs); or calcium blockers, Batsis says.
Beta-blockers that may cause weight gain include:
- Acebutolol (Sectral)
- Atenolol (Tenormin)
- Bisoprolol (Zebeta)
- Metoprolol (Lopressor, Toprol XL)
- Nadolol (Corgard)
- Nebivolol (Bystolic)
- Propranolol (Inderal LA, InnoPran XL)
- Oral corticosteroids
Oral corticosteroids are prescribed for everything from severe allergies and rashes to rheumatoid arthritis, but they come with side effects — among them, weight gain. The culprit? Fluid retention.
What to do: To avoid weight gain, the experts recommend a diet rich in low-glycemic foods such as fruits and vegetables, beans, minimally processed grains, low-fat dairy and nuts, all of which are “slowly digested and absorbed, causing a slower and smaller rise in blood sugar levels.”
Avoid unnecessary use of corticosteroids, which are commonly prescribed at urgent care centers for allergies and upper respiratory infections.
- Migraine Medications
Talk about a vicious cycle: If you’re overweight and suffer from migraines, extra weight puts you at greater risk for more frequent and more severe migraines!
Migraine medications that may cause weight gain include:
- Propranolol (Inderal)
- Divalproex sodium (Depakote)
According to the American Migraine Foundation, people at a healthy weight who experience migraines have about a 3 percent chance of developing chronic headaches. For people who are overweight and for people with obesity, the chance of chronic migraine is three to five times greater.
What to do: If you’re on a migraine-preventive medication that’s causing weight gain, talk to your doctor about switching to one that has the potential to suppress appetite, such as topiramate (Topamax), zonisamide (Zonegran), protriptyline (Vivactil), along with phentermine plus topiramate (Qsymia).
- Antihistamines
It’s easy to assume that over-the-counter meds don’t carry serious side effects because they’re so readily available. But just because something is available without a prescription doesn’t mean it’s risk-free. Research suggests that taking an antihistamine on a regular basis — to treat allergies, for instance — can result in weight gain.
Antihistamines that may cause weight gain include:
- Cyproheptadine (Periactin)
- Cetirizine (Zyrtec)
- Fexofenadine (Allegra)
- Desloratadine (Clarinex)
Why? Histamine, a chemical in the body known to be a key player in allergic responses, decreases hunger by affecting the appetite control center in the brain, so it makes sense that an antihistamine would have the opposite effect, interfering with the “I’m full” signal coming from the rest of the body, according to the Obesity Medicine Association.
What to do: Talk to your doctor about which antihistamine may be best for you. Generally, if your allergies are sinus related, you can try nasal saline or a steroid nasal spray, as they don’t have systemic side effects.
- Anti-epilepsy drugs
A review of research published in Epilepsia suggests that people with epilepsy exercised less and tended to have obesity even if their seizures were under control. Conventional wisdom suggests that a fear of doing anything that could provoke a seizure would figure into why people with epilepsy are less inclined to be physically active. But anti-epilepsy drugs have been shown to play a significant role in weight gain:
- Valproic acid (Depakene)
- Gabapentin (Neurontin)
- Pregabalin (Lyrica)
- Possibly carbamazepine (Carbatrol)
What to do: If you’re taking any of these and experiencing weight gain, talk to your doctor about possible alternatives such as topiramate (Topamax) or zonisamide (Zonegran), both of which are also prescribed for migraines and associated with weight loss.
- Antipsychotics
People with mental health disorders are two to three times more likely to be obese than the general population. A review of research examining antipsychotic medicine explains why: Most of those drugs cause weight gain. Over the course of treatment, around 7 in 10 patients will gain weight — rapidly in the initial period after starting these meds, but it continues over the long term. The risk appears to be highest with:
- Olanzapine (Zyprexa)
- Clozapine (Clozaril)
Making matters worse, these types of drugs impair glucose function and increase cholesterol and triglycerides, putting patients more at risk for developing metabolic syndrome, according to a review of research in Neuropsychiatric Disease and Treatment.
What to do: If you’re taking an antipsychotic for bipolar disorder, schizophrenia or depression and you’re experiencing weight gain, talk to your doctor about newer medications on the market. “They tend to have lower risk of weight gain,” Batsis says. Keep in mind that everybody is different, he hastens to add. “While we can generalize, these medications may affect different individuals in different ways.”
