How much weight can you gain from taking these antidepressants?

Get inspired by our weekly roundup of tips for living simply and fulfillingly. Sign up for CNN's Life, But Better newsletter for information and tools to improve your health.

CNN
—

Antidepressants It could be life-saving for many people struggling with a number of mental illness diagnoses. anxiety, depression, Obsessive-compulsive disorderpanic disorder, Social phobia and Post-traumatic stress disorder. However, taking these mood-altering substances can cause an unpleasant side effect in some people: weight gain.

Although many people don't put on excess weight, doctors say concerns about weight gain are a major reason people hesitate to take antidepressants for their mental health. Weight gain This is why some people stop taking medication even though it helps reduce their depression and anxiety while they are taking it.

New research shows Weight gain On average, people taking the eight most commonly prescribed antidepressants are likely to experience these side effects.

One of the most widely prescribed antidepressants, sertraline (also known as Zoloft and Rustral), has been associated with an average weight gain of about half a pound (0.2 kilograms) over six months, which rose to 3.2 pounds (1.46 kilograms) over 24 months, according to the study.

For comparison, researchers found that people taking escitalopram, known by the brand names Lexapro and Cipralex, had an average 15 percent higher risk of gaining 5 percent or more of their baseline weight over six months than people taking sertraline. For paroxetine, sold under the names Paxil, Allopax, Pexeva, Seroxat, Celeupin and Brisdale, the risk was 14 percent, the study found.

The study found that duloxetine, sold under the brand names Cymbalta, Loxentia and Ientrib, was associated with a 10% increased risk of patients gaining more than 5% of their baseline body weight compared with sertraline.

Weight gain of 5 percent or more from baseline is considered clinically important for health, said Joshua Pettimer, an assistant professor of population medicine at Harvard Pilgrim Health Care Institute and Harvard Medical School in Boston and lead author of the study.

The average weight of a typical adult is 1-2 pounds per yearOver time, this can lead to obesity. Experts say this weight gain can be caused by lack of exercise, stress, lack of sleep, poor dietary choices like eating too many processed foods, and medications.

the study, Released on Monday A study published in the Annals of Internal Medicine compared weight gain in more than 183,000 people using prescriptions and weight data from electronic medical records. Researchers looked at weight gain in people aged 18 to 80 at six, 12, and 24 months after they first started taking an antidepressant.

When the data was analyzed by pounds and kilograms of weight gain, people taking escitalopram and paroxetine gained an average of 1.4 pounds (0.63 kilograms) by 6 months. By 24 months, those taking escitalopram had gained 3.6 pounds (1.63 kilograms) and those taking paroxetine had gained about 3 pounds (1.33 kilograms).

Duloxetine was associated with a mean weight gain of 1.2 pounds (0.55 kilograms) at 6 months and 1.7 pounds (0.78 kilograms) at 24 months.

“In our study, the average baseline weight was 84 kg, or about 185 pounds,” Pettimer said in an email. “This means that in our study, a 5% increase in weight translated into an average weight gain of 4.2 kg, or about 9 pounds.”

However, the study did not find a significantly higher or lower risk for citalopram (sold as Celexa), fluoxetine (sold as Prozac), or venlafaxine (sold as Effexor, Effexor XR, Vensil, Vencalm, Benralix, and Benlabreu) ​​when compared with sertraline.

“It's important to remember that these are averages. Many people will not gain weight, but others may gain a lot,” said Dr. Roy Perlis, vice director of psychiatric research at Massachusetts General Hospital and professor of psychiatry at Harvard Medical School in Boston. A similar study was conducted in 2014. He was not involved in the new study.

“Still, working with averages and seeing that they align well with past studies can at least give people a sense of what to expect,” Perlis said in an email.

Pettimard said that while many patients taking antidepressants would rather avoid weight gain than want it, not all of them view weight gain negatively — for example, mirtazapine is an antidepressant that is sometimes used to treat eating disorders.

“We did not look at mirtazapine in this study because it is not considered a common first-choice drug for new users of antidepressants,” he said.

A study found that one antidepressant contributed to small weight loss over six months.

“Bupropion (Wellbutrin and Zyban) on average “Compared with sertraline, there was a 15% lower risk of clinically meaningful weight gain,” Pettimard said.

“Our study did not investigate why bupropion results in less weight gain than other antidepressants, but other studies have similarly concluded that bupropion results in less weight gain than other common antidepressants,” he added.

When weight loss was analyzed in pounds or kilograms, people taking bupropion lost about a quarter of a pound (0.01 kilogram) in six months but gained 1.2 pounds (0.56 kilograms) in 24 months, the study found.

As for why antidepressants lead to weight gain, the science isn't clear yet, Perlis says.

“Surprisingly, we don't know exactly how antidepressants affect weight change. Even worse, we know so little about who is most likely to gain or lose weight that we can't make good predictions in advance,” he said.

It's important to note, Perlis says, that some people with depression lose weight and lose their appetite, but “as their depression or anxiety improves, some people may regain the weight they lost.”

The best way to manage side effects is to anticipate them, experts say.

“Patients who are concerned about weight gain should have an open and honest discussion with their doctor about their concerns,” Pettimer said.

“There are many clinical factors that determine which medication is appropriate for a particular patient,” Pettimer says, “including the patient's clinical symptoms, medical history, other medications they are already taking, and any side effects they may be concerned about.”

Doctors need to consider all these factors when deciding which treatment is best, but patients can try to avoid weight gain by following healthy eating habits and exercising regularly, he added.