Key takeaways:
Paroxetine (Paxil) is a prescription medication that treats several mental health conditions. But it might cause weight gain, which is common with some antidepressants.
Weight gain is more likely with higher doses of paroxetine and when it’s used for longer than 6 months. Weight gain isn’t a common side effect of Brisdelle, a low-dose version of paroxetine.
Exercising, optimizing your nutrition, and tracking your body weight over time can help you maintain or reach your target body weight.
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You’ve likely heard that some medications can cause weight gain. Or, perhaps, you’ve taken a medication in the past and noticed weight changes soon after. Many medications — often those that affect your metabolism — can unfortunately have this effect.
One popular group of medications that can cause weight gain are selective serotonin reuptake inhibitors (SSRIs). These medications are popular first-choice options to treat depression and many types of anxiety.
Within this class of medications, paroxetine (Paxil) is considered to be the most likely to cause weight gain. But how much weight gain should you actually expect?
Below, we’ll discuss the connection between paroxetine and weight gain. We’ll also walk through preventing and managing possible weight changes.
Is weight gain a side effect of paroxetine?
Yes, it’s possible to gain weight while taking paroxetine. In early clinical trials of paroxetine, weight gain was observed in at least 1% of people who took the medication.
More recent data estimates that it’s even more common than this, but specific numbers vary by study. Still, health experts generally agree that paroxetine is more likely to cause weight gain than other SSRIs.
This side effect is most likely to affect people who take the medication for a long period of time, typically more than 6 months.
How much weight gain is normal with paroxetine?
No specific amount of weight gain with paroxetine is “normal.” The specific amount varies for everyone.
For instance, one review found that people who took paroxetine for 6 to 8 months gained an average of about 4% of their body weight. Meaning, if you weigh 200 lbs, paroxetine could lead to an extra 8 lbs.
In another study, people who took paroxetine for 1 year gained an average of 2 lbs, but some people gained up to 14 lbs.
Keep in mind: Not everyone who takes paroxetine will experience weight gain. This is a misconception that can sometimes discourage people from taking the medication. When they’re needed, medications like paroxetine offer an effective and empowering way to treat conditions like depression.
Why do antidepressants like SSRIs cause weight gain?
SSRIs work to regulate serotonin. Serotonin is a brain chemical that helps regulate energy, mood, and digestion. But boosting the amount of serotonin in your brain with antidepressant medications can sometimes be confusing to your body. In some cases, this can lead to weight gain.
The reason why this happens isn’t fully known. But there are a few hypotheses. One theory is that your appetite may change, which can lead to weight gain. Depression itself can also affect certain behaviors negatively. Changes in your motivation, exercise routine, and energy levels can also play roles.
Does Brisdelle also cause weight gain?
No, weight gain isn’t a reported side effect of Brisdelle. Brisdelle is another brand-name version of paroxetine, but it’s used for the treatment of hot flashes associated with menopause.
Brisdelle is a low-dose version of paroxetine. Each oral capsule contains 7.5 mg of paroxetine, whereas other versions of paroxetine contain 10 mg to 40 mg per pill.
The higher the dose of paroxetine, the more likely you are to experience weight gain.
Can weight gain be prevented when taking paroxetine?
In many cases, yes. A few steps can help prevent weight gain from paroxetine (or make it less likely). These steps can also help manage possible weight fluctuations you could see.
Talk to your healthcare team about trying these habits:
Breaking up your meal schedule into smaller meals throughout the day
Documenting your body weight on a weekly basis to notice any changes or trends
Keeping a food diary and monitoring changes in your eating habits
Incorporating more exercise into your daily routine when feasible, even if it just means taking the stairs instead of the elevator or parking farther away than you usually do
Talking to a nutritionist about adjusting your diet, if needed
What other paroxetine side effects can you expect?
Paroxetine is generally well-tolerated. But like with all medications, side effects can still occur. They also vary from person to person. They depend on your dose, what health condition you’re taking it for, and your lifestyle. Still, some side effects are more common than others.
The following side effects happened to more than 10% of people in paroxetine’s initial clinical trials:
Nausea
A lack of energy
Dry mouth
Headache
Constipation
Diarrhea
Dizziness
Insomnia
Sleepiness
Sweating
Certain sexual problems
Rare but potentially serious side effects can also happen while taking paroxetine. If you experience any of the following side effects, seek emergency medical attention right away:
Signs or symptoms of a stomach bleed, such as black stool, bright red blood in your vomit, or abdominal cramps
Suicidal thoughts and behaviors
Confusion
Shivering or changes in your body temperature
Abnormal heart rhythm
Seizures
What is paroxetine used to treat?
Paroxetine is a prescription-only oral antidepressant medication that treats various mental health conditions in adults.
Paroxetine is FDA approved to treat:
There are a couple versions of paroxetine, though. In addition to the standard immediate-release (IR) version, there’s also a controlled-release (CR) formulation. Certain formulations are preferred in different situations. For example, only the CR version is approved to treat PMDD. Your prescriber will ultimately select the most appropriate form of paroxetine for you to take.
Frequently asked questions
Yes, paroxetine may make it harder to lose weight. But this isn’t set in stone. Several factors can influence weight loss or weight gain aside from medication. And it’s still possible to lose weight while taking a medication that’s been linked to weight gain.
Some of the most common side effects of paroxetine are nausea, headache, and a lack of energy. Dry mouth, constipation, and certain sexual problems are also relatively common. Specific side effects vary by person, though, and the likelihood of certain issues varies based on what you're taking it for.
Yes, paroxetine may make it harder to lose weight. But this isn’t set in stone. Several factors can influence weight loss or weight gain aside from medication. And it’s still possible to lose weight while taking a medication that’s been linked to weight gain.
Some of the most common side effects of paroxetine are nausea, headache, and a lack of energy. Dry mouth, constipation, and certain sexual problems are also relatively common. Specific side effects vary by person, though, and the likelihood of certain issues varies based on what you're taking it for.
The bottom line
Paroxetine (Paxil) is a prescription medication that treats many health conditions. It’s generally well-tolerated, but weight gain can be a concern for some people. Weight gain is mostly seen in people who use higher doses and when it’s used for more than 6 months at a time. However, it’s not typically seen among people who take Brisdelle, a low-dose version of paroxetine.
There are a few ways to prevent and manage weight gain while taking paroxetine. Do your best to think about your physical activity, track your eating habits, and document your weight at least once a week. Be sure to talk to your healthcare team about any weight changes you notice or any other bothersome side effects you experience.
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References
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