According to a recent study published in the Annals of Internal Medicine, some antidepressant medications are more likely than others to cause weight gain. The study, led by researchers from Harvard Medical School and Harvard Pilgrim Health Care Institute, analyzed electronic health record data of over 183,000 new antidepressant users from eight U.S. health systems between 2010 and 2019.
The researchers compared weight gain among patients prescribed several different first-line antidepressants and those taking sertraline, which is the most commonly prescribed antidepressant. They found that users of escitalopram (Lexapro) and paroxetine (Seroxat) gained roughly 1 pound more than those on sertraline after six months. Escitalopram and paroxetine users were also 10% to 15% more likely to gain at least 5% of their baseline weight than sertraline users.
On the other hand, patients prescribed bupropion (Wellbutrin) saw the least amount of weight gain among those taking first-line antidepressants. Fluoxetine (Prozac) was not associated with a change in weight after six months compared with sertraline.
The study offers a more granular look at the impact of different antidepressant medications on weight gain, as previous studies have only provided averages. The researchers noted that while the overall effect may seem small, it affects some patients more than others.
Lead researcher Joshua Petimar told Axios that the study aims to give both providers and patients more information to make informed decisions about their antidepressant use.
The study is part of a series of examinations Petimar's team is planning on how patients' weight is affected by certain medications, including antidepressants taken by children and adolescents, as well as drugs for psychosis, diabetes, hypertension and seizures.