Antidepressant Side Effect Tolerance Calculator
Find Your Best Antidepressant Match
This tool helps you compare bupropion and SSRIs based on your specific concerns and side effect tolerance.
Your Personalized Recommendation
Based on the evidence from real-world use:
- Sexual side effects:
- Weight changes:
- Energy level:
- Anxiety:
- Seizure risk:
When you’re struggling with depression, finding the right medication isn’t just about whether it works-it’s about whether you can live with how it makes you feel. Two of the most commonly prescribed antidepressants, bupropion and SSRIs, work in completely different ways, and that shows up in their side effects. If you’ve ever felt numb, sluggish, or like you lost your sex drive on an SSRI, you’re not alone. And if you’ve been told bupropion might help, but you’re scared of seizures or anxiety spikes, you’re not alone there either. This isn’t a textbook comparison. It’s what actually happens to people taking these drugs day after day.
How They Work (And Why It Matters)
Bupropion, sold as Wellbutrin or Zyban, doesn’t touch serotonin at all. Instead, it boosts norepinephrine and dopamine-two brain chemicals linked to energy, focus, and motivation. That’s why some people feel more awake, sharper, or even mildly stimulated on it. SSRIs like sertraline (Zoloft), escitalopram (Lexapro), and fluoxetine (Prozac) work by increasing serotonin. Serotonin helps with mood, but it also controls sleep, digestion, and sexual function. That’s why side effects like nausea, drowsiness, and low libido show up so often.
It’s not about which one is “better.” It’s about which side effects you can tolerate. A 2002 meta-analysis found both classes work equally well for depression. But when you look at how people feel while taking them, the differences are stark.
Sexual Side Effects: The Biggest Dealbreaker
If you’ve ever stopped an SSRI because you lost interest in sex, you’re in the majority. Studies show 30% to 70% of people on SSRIs experience sexual side effects. Paroxetine (Paxil) hits the highest end-up to 76% of users report problems with arousal, orgasm, or desire. That’s not rare. That’s the norm.
Bupropion? About 13% to 15% of users report sexual side effects. That’s not zero-but it’s a big drop. One 2015 study found that 67% of people who switched from an SSRI to bupropion saw their sex drive come back. Another 48% improved when bupropion was added to their SSRI. Real people on Reddit and Drugs.com say the same thing: “I finally felt like myself again,” “Sex wasn’t a chore anymore.”
On Drugs.com, 47% of negative reviews for Lexapro mention sexual dysfunction. For bupropion? Only 12% do. That’s not a small difference. That’s life-changing for many.
Weight: Gain vs Loss
SSRIs often lead to weight gain. Paroxetine and sertraline can add 2.5 to 3.5 kilograms over six to twelve months. People report gaining 10, 15, even 25 pounds-sometimes without changing their diet or exercise. It’s not just about appearance. It’s about self-esteem, diabetes risk, and feeling trapped in your own body.
Bupropion does the opposite. In clinical trials, people lost an average of 0.8 to 1.2 kilograms over the same time. A 2009 study found that bupropion XL at 400 mg/day led to a 7.2% weight loss over 24 weeks. On Drugs.com, users say things like, “No weight gain after 18 months,” or “I lost 12 pounds without trying.”
If weight is a concern-whether because of past struggles, diabetes, or just wanting to feel in control-bupropion gives you a real advantage.
Sleep and Energy: Awake vs Asleep
SSRIs can make you tired. Fluoxetine might keep you awake at first, but many people end up feeling sluggish during the day. Paroxetine is especially sedating. That’s why some doctors prescribe it at night.
Bupropion is the opposite. It’s one of the few antidepressants that can actually help you feel more alert. In studies, it’s associated with a 73% lower risk of daytime sleepiness compared to SSRIs. People describe it as “finally feeling like I’m not drugged,” or “I can actually get through my workday.”
But here’s the catch: that same energy can backfire. For people with anxiety, bupropion can make things worse. It can cause restlessness, jitteriness, or even panic attacks. A 2017 study found that 28% of patients with anxiety disorders stopped bupropion because of increased anxiety. Only 12% did the same with SSRIs.
Seizure Risk: The Hidden Warning
Bupropion carries a small but real risk of seizures. At 300 mg per day, it’s about 0.1%. At 400 mg, it jumps to 0.4%. That’s why doctors never prescribe it to people with a history of seizures, eating disorders, or those taking other medications that lower the seizure threshold. Even if you’ve never had a seizure, combining bupropion with certain antidepressants or stimulants can increase the risk.
SSRIs? Seizure risk is around 0.02% to 0.04%. Almost negligible. If you’ve had a seizure before, or if you’re at risk, SSRIs are the safer choice.
Blood Pressure and Heart Health
Bupropion can raise systolic blood pressure by 3 to 5 mmHg on average. That’s not huge, but it’s enough to matter if you already have high blood pressure or heart disease. Doctors recommend checking your blood pressure every 2 to 4 weeks when you start.
SSRIs usually don’t affect blood pressure-or may even lower it slightly. For people with hypertension, that’s a plus.
What Real People Say
On Reddit’s r/mentalhealth, one user wrote: “Switched from Lexapro to Wellbutrin after 2 years of zero sex drive. Within 3 weeks, my libido returned. Now I can’t sleep.” Another said: “I gained 25 pounds on Zoloft. On bupropion, I lost 18. But now I’m jittery all day.”
On Drugs.com, bupropion has a 7.4/10 rating. 68% say it helped. The biggest complaints? Anxiety, insomnia, and ringing in the ears. SSRIs like Lexapro have a 6.8/10 rating. The biggest complaints? Sexual dysfunction and weight gain.
One 2021 survey found that 63% of patients preferred bupropion for fewer sexual side effects. But 71% of patients with anxiety preferred SSRIs. It’s not about which drug is better. It’s about which side effects you can live with.
When to Switch or Add
If you’re on an SSRI and can’t stand the side effects, switching to bupropion is a common and often successful move. But don’t just stop your SSRI cold. For fluoxetine (Prozac), you need a 2-week washout because it sticks around in your system for days. For others, a week is enough. Going too fast can cause withdrawal symptoms-dizziness, brain zaps, nausea.
Some doctors add bupropion to an SSRI to fix sexual side effects. Studies show 70% to 80% of patients improve. But this combo increases seizure risk and can cause serotonin syndrome (a rare but dangerous condition). It’s not for everyone. Only do this under close medical supervision.
Who Should Avoid Bupropion
Bupropion isn’t for everyone. Avoid it if you:
- Have a seizure disorder
- Have an eating disorder (anorexia or bulimia)
- Are taking other medications that lower seizure threshold (like antipsychotics or stimulants)
- Have uncontrolled high blood pressure
- Are already on another antidepressant and haven’t done a proper washout
Also, if you have severe anxiety, panic disorder, or agoraphobia, bupropion might make things worse. SSRIs are usually better here.
What About Dosing?
Bupropion is usually started at 150 mg once daily, then increased to 300 mg after a week. Never go above 450 mg per day. Higher doses increase seizure risk without more benefit. Extended-release forms (like Wellbutrin XL or Aplenzin) let you take it once a day, which helps with adherence.
SSRIs vary. Sertraline starts at 50 mg, escitalopram at 10 mg, fluoxetine at 20 mg. Doses can be increased slowly over weeks. Some people need higher doses. Others do fine on low ones.
What’s New in 2025?
Pharmacogenetic testing is becoming more common. Some labs test your genes to predict if you’re likely to have bad side effects from SSRIs. If you’re a “slow metabolizer,” you’re more likely to get nauseated or feel emotionally flat. In those cases, bupropion is often the better first choice. The 2023 GUIDED trial showed that using genetic testing to guide antidepressant choice improved remission rates by 14.2%.
The market is shifting too. Bupropion makes up about 10% of antidepressant prescriptions-still far behind SSRIs, which account for 70%. But prescriptions for bupropion for sexual dysfunction have tripled since 2010. More doctors are thinking about side effects before they write a script.
Final Takeaway
There’s no perfect antidepressant. But there is a best one for you. If sexual side effects or weight gain ruined your experience with SSRIs, bupropion could be your answer. If anxiety, insomnia, or seizure risk scares you, SSRIs might be safer. It’s not about which drug is stronger. It’s about which side effects you can handle-and which ones will make you quit.
Talk to your doctor. Bring your list of side effects. Ask: “Which one is least likely to make me feel worse?” That’s the question that matters most.
Is bupropion better than SSRIs for depression?
Bupropion and SSRIs work equally well for depression, according to multiple studies. The difference isn’t in how well they lift mood-it’s in how they make you feel while doing it. Bupropion is often preferred if you struggle with sexual side effects, weight gain, or daytime fatigue. SSRIs are often better if you have anxiety or a history of seizures.
Can bupropion help with SSRI-induced sexual dysfunction?
Yes. Studies show that switching from an SSRI to bupropion improves sexual function in about 67% of cases. Adding bupropion to an existing SSRI helps 70-80% of people in open-label trials. It’s one of the most reliable fixes for this common problem.
Does bupropion cause weight gain?
No-most people lose a small amount of weight on bupropion. Clinical trials show an average loss of 0.8-1.2 kg over 6-12 months. Some people lose more, especially at higher doses. This is the opposite of most SSRIs, which often cause weight gain.
Why do SSRIs cause sexual side effects?
SSRIs increase serotonin, which helps mood but also suppresses sexual arousal and orgasm. This effect is dose-dependent and varies by drug-paroxetine is the worst offender, while fluoxetine and escitalopram are slightly less likely to cause issues. The problem affects 30-70% of users and often persists as long as you’re on the medication.
Can I take bupropion and an SSRI together?
Yes, but only under close medical supervision. Combining them can help fix sexual side effects from SSRIs, but it increases the risk of seizures and serotonin syndrome-a rare but dangerous condition. Always tell your doctor about all medications you’re taking. Never combine them without a clear plan and monitoring.
Which antidepressant has the least side effects?
There’s no single answer. Bupropion has fewer sexual and weight-related side effects but carries a higher seizure risk and can worsen anxiety. SSRIs are less likely to cause seizures but often cause nausea, drowsiness, and sexual dysfunction. The “least side effects” depends on your body, your symptoms, and your priorities. Personalized treatment matters more than general rankings.
