Key takeaways:
Paroxetine (Paxil) is a medication that treats various 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 is not a common side effect of Brisdelle, a low-dose version of paroxetine.
Exercising, monitoring your eating habits, and tracking your weight can help prevent or manage weight gain.
Save on related medications
You’ve likely heard that some medications can cause weight gain. Or, perhaps, you’ve taken a medication in the past and noticed some 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.
What is paroxetine used to treat?
Paroxetine is a prescription-only antidepressant medication that treats various mental health conditions in adults. Paroxetine is approved to treat:
Panic disorder (PD)
Social anxiety disorder (SAD)
General anxiety disorder (GAD)
However, know that there are a couple versions of paroxetine. In addition to the standard immediate-release (IR) version, there’s also a controlled-release (CR) formulation. This difference can play a role when treating certain health conditions. For example, only the CR version is approved to treat PMDD.
How does paroxetine work?
Depression has many possible causes, including your genetics and changes in your brain chemistry. Paroxetine and other SSRIs work to raise the amount of a chemical in your brain known as serotonin. This can help promote feelings of mental balance and improve symptoms of depression or anxiety.
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. A few more recent studies estimate that it’s even more common than this, but specific numbers vary by study. However, health experts generally agree that paroxetine is more likely to cause weight gain than other SSRIs.
This side effect is more likely to happen when paroxetine is taken for a long period of time, typically more than 6 months.
How much weight gain is normal with paroxetine?
No amount specifically 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 that not everyone who takes paroxetine will experience weight gain. This is a misconception that can sometimes discourage people from taking this 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?
As mentioned, SSRIs work to regulate serotonin. Serotonin is a brain chemical that helps control 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 theories. For instance, 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 is not a reported side effect of Brisdelle. Brisdelle is another name-brand 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. These steps can also help manage possible weight fluctuations you could see. Talk to your healthcare provider about trying these habits:
Breaking up your meal schedule into smaller meals throughout the day
Documenting your 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
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 using it to treat, 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 medical attention right away:
Signs 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
The bottom line
Paroxetine is an oral 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 lower-dose version of paroxetine.
There are a few ways to prevent and manage weight gain while taking paroxetine. It’s important 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 provider about any weight changes you notice or any other bothersome side effects you experience.
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References
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