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Key takeaways
Trintellix is an antidepressant approved for the treatment of major depressive disorder (MDD). As a serotonin modulator, it’s less likely than many other antidepressants to cause weight gain, but serotonin levels in the brain can affect some people’s appetite and metabolism.
Weight gain is not a commonly reported side effect of Trintellix, but some people do experience weight changes, including weight gain, when taking it for longer periods of time.
If you experience Trintellix weight gain, talk to your healthcare provider about managing this side effect while treating your MDD symptoms.
Trintellix (vortioxetine) is a relatively new antidepressant medication that was approved by the Food & Drug Administration (FDA) in 2013 for the treatment of major depressive disorder (MDD), a severe and persistent type of depression, in adults. Clinical trials have shown Trintellix to be effective in treating MDD symptoms, with similar side effects to other common antidepressants.
Because many types of antidepressants include weight gain as a possible side effect, you may be wondering if the same is true for Trintellix. The manufacturer of Trintellix, Takeda Pharmaceuticals, doesn’t include weight gain as a possible side effect on the drug label. But in the years since its approval, some people have reported gaining weight while taking it. So, does Trintellix cause weight gain or not? Here’s what the experts say.
How does Trintellix work?
Trintellix is generally considered part of a class of antidepressants called serotonin modulators, though some experts also refer to it as an atypical antidepressant. It’s not known exactly how Trintellix works, other than that it balances out the amount of serotonin in your brain. Serotonin is a neurotransmitter responsible for regulating many different functions, including mood, sleep, libido, blood clotting, and digestion.
According to Mahreen Ahmed, MD, a psychiatrist with Mindpath Health, Trintellix’s influence on serotonin levels could affect appetite and metabolism, causing some people to experience weight changes, but it’s still considered a weight-neutral drug that isn’t known to directly impact weight.
Does Trintellix cause weight gain?
Most people taking Trintellix won’t experience weight gain. In fact, Dr. Ahmed says Trintellix is one of the least likely antidepressants to cause weight changes, especially compared to alternatives like tricyclic antidepressants (TCAs), monoamine oxidase inhibitors (MAOIs), or selective serotonin reuptake inhibitors (SSRIs).
That said, it’s not impossible to gain weight while taking Trintellix. In initial short-term clinical trials, weight gain was not found to be a side effect, but in a long-term 2013 study, more than 4% of participants reported weight gain while taking Trintellix for about one year. The average weight gain between the beginning and end of the study was around 1.4 pounds. Since then, Takeda Pharmaceuticals has updated its side effect information to acknowledge that weight gain was reported after the drug received approval by the FDA.
It’s worth noting that other factors could contribute to a 1.4-pound weight gain while taking Trintellix that don’t actually relate to the drug. According to Nick Bach, PsyD, a licensed clinical psychologist in Louisville, Kentucky, depression itself can impact your metabolism, appetite, and activity levels, especially if you are undereating, overeating, or exercising less as a result of your symptoms.
Common Trintellix side effects
The most common side effects of Trintellix are nausea, vomiting, and constipation. Nausea is especially common, affecting about 25% of people on Trintellix, though most people find that their nausea decreases the longer they’re on the drug.
Some other less common side effects of Trintellix include diarrhea, headache, dry mouth, dizziness, and itching. Strange dreams and sexual side effects, like decreased sex drive, have also been reported.
Serious Trintellix side effects
Like all medications, there are some potentially serious side effects you could experience while taking Trintellix, including:
- Allergic reaction, which may include hives, rash, swelling, or anaphylaxis
- Serotonin syndrome, especially if you are taking other medications that affect serotonin levels in the brain
- Abnormal bleeding
- Hyponatremia, or low blood sodium
- An eye problem called angle-closure glaucoma, especially in people with other eye disorders
Trintellix also has a boxed warning (also called a black box warning) for suicidal thoughts and behaviors in children, teens, and young adults. Like all antidepressants, Trintellix could make your depression symptoms worse instead of better. Trintellix can also trigger a manic or depressive episode in people with a family history of bipolar disorder, though this is rare.
How to manage Trintellix side effects
Many Trintellix side effects decrease the longer you are on the medication, so if you’re experiencing GI symptoms or weight changes, it may be temporary. In general, you can manage Trintellix side effects by always taking the medication as it’s prescribed, and don’t stop suddenly or skip doses.
If you experience Trintellix weight gain, Dr. Bach says a lower dose that still relieves your MDD symptoms may be an option. However, never decrease or change your dose without first asking your healthcare provider. They can determine whether a dose adjustment is a safe option for you or if a different treatment is needed.
RELATED: What happens if I suddenly stop taking Trintellix?
Dr. Ahmed also recommends reaching out to your healthcare provider if you’re gaining weight on Trintellix. They can help you consider other drugs to manage your MDD or find healthy ways to manage your weight while remaining on Trintellix, like increasing your physical activity and taking a close look at your nutrition and diet.
Trintellix alternatives
According to Dr. Bach, there are some alternatives to Trintellix that are unlikely to cause weight gain, including Wellbutrin (buproprion) and Viibryd (vilazodone). Wellbutrin is considered a weight-neutral medication and is even associated with weight loss in some people, he explains, and Viibryd is an SSRI that offers similar benefits for people with MDD but also has a lower risk of weight gain.
Bottom line
It’s unlikely you’ll experience weight gain from Trintellix itself, although weight gain is possible during treatment. Trintellix is part of a class of antidepressants that is associated much less with weight gain than other drugs like SSRIs and MAOIs. However, some people have reported weight gain while taking Trintellix, and at least one long-term study confirms that a small number of people may experience weight changes on this medication.
If you think you are gaining weight on Trintellix, talk to your healthcare provider. They can help you safely manage your MDD symptoms and reduce the likelihood of weight gain. This may include switching medications or lowering your dose of Trintellix, but you should never stop or change your dosage of Trintellix without consulting your provider first.
RELATED: How to save on Trintellix
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