Bupropion Side Effects: Insomnia, Anxiety, and Seizure Risk Explained

When you're struggling with depression and tired of antidepressants that leave you feeling emotionally flat, sexless, or heavier than before, bupropion (sold as Wellbutrin, Zyban, or Aplenzin) often feels like a breath of fresh air. It doesn’t crush your libido like SSRIs do. It might even help you lose weight. But for every person who says, "This finally let me live again," there’s someone else who says, "I couldn’t sleep for weeks," or "I felt like I was going to have a seizure." If you’re considering bupropion-or already taking it-here’s what you really need to know about its three most talked-about side effects: insomnia, anxiety, and seizure risk.

Why Bupropion Is Different

Most antidepressants, like Prozac or Zoloft, work by boosting serotonin. Bupropion doesn’t. Instead, it targets dopamine and norepinephrine-two brain chemicals tied to energy, focus, and motivation. That’s why it’s often chosen for people who feel sluggish, unmotivated, or mentally foggy. It’s also the only antidepressant FDA-approved for smoking cessation. But this different mechanism comes with trade-offs. While it avoids sexual side effects (only 1-6% of users report them, versus 30-70% with SSRIs), it’s more likely to cause sleep problems, jitteriness, and, in rare cases, seizures.

Insomnia: The Sleep Killer

About 19% of people taking bupropion report trouble sleeping. That’s higher than most other antidepressants. For some, it’s mild-just a little harder to fall asleep. For others, it’s a full-blown nightmare. Reddit threads are full of stories like: "I took my 150mg at 8 a.m. and still couldn’t sleep until 3 a.m. for three weeks straight." Why does this happen? Bupropion stimulates the brain. It’s like drinking two cups of coffee after lunch. Even if you take it in the morning, the drug stays active in your system for hours. The sustained-release (SR) version peaks around 3 hours after taking it. The extended-release (XL) version lasts longer but hits peak levels slower-around 5 hours. That’s why doctors always say: never take bupropion after 4 p.m. If you’re on the SR version, don’t even take it after noon.

What works for most people? Move your dose to early morning. Mayo Clinic data shows 68% of patients who switched from afternoon to morning dosing saw sleep improve within days. If insomnia persists, your doctor might lower your dose or suggest a short-term sleep aid. But don’t try to "power through" it. Chronic sleep loss can make depression worse, not better.

Anxiety: The Jittery Start

It’s common to feel more anxious in the first week or two of starting bupropion. About 20-25% of users report increased nervousness, restlessness, or agitation. Some describe it as "my brain won’t turn off," "I can’t sit still," or "I feel like I’m on edge all day." This isn’t a sign the drug isn’t working-it’s a side effect of the sudden dopamine and norepinephrine surge. Your brain is adjusting. In most cases, these symptoms fade within 10-14 days. But for about 1 in 5 people, the anxiety doesn’t ease. That’s when it becomes a problem.

Here’s what to watch for: If your anxiety spikes to panic attacks, racing heart, or feeling like you’re losing control, talk to your doctor. Don’t wait. Some providers will temporarily add a low-dose benzodiazepine (like lorazepam) for the first two weeks to help you get through the adjustment period. Others will switch you to a slower titration schedule-starting at 75mg instead of 150mg. Never increase your dose on your own. Pushing through severe anxiety can make it worse.

Seizure Risk: The Silent Danger

This is the most serious side effect-and the one most people don’t know about until it’s too late.

At normal doses (under 450mg per day), the chance of a seizure is about 0.4%. That’s low-but still 40 times higher than the general population. At doses over 600mg per day, that risk jumps to 2-5%. That’s not a small number. It’s a real, life-threatening risk.

Who’s most at risk? People with:

• A history of seizures or head injury
• Eating disorders (anorexia, bulimia)
• Severe liver disease
• Alcohol or drug dependence
• Taking other medications that lower seizure threshold (like antipsychotics or certain antibiotics)

The biggest mistake? Doubling up on doses to "feel it faster." One case report from 2023 describes a 35-year-old woman who increased her bupropion SR from 150mg to 300mg in one week. Two days later, she had her first seizure. She had no prior history. She was healthy. She just thought, "More must be better." The extended-release (XL) version is safer because it releases the drug more slowly, reducing dangerous spikes in blood levels. But even XL can cause seizures if misused. Never take more than 400mg per day of XL, or 450mg per day of SR. And never combine different formulations-like taking XL in the morning and SR at night. That’s how people overdose.

What to Do If You’re Already on Bupropion

If you’re currently taking bupropion and experiencing side effects, here’s what to do:

1. Track your symptoms. Write down when you take your dose, when you feel anxious, and when you can’t sleep. Bring this to your doctor.
2. Check your timing. Are you taking it after 4 p.m.? Move it to morning.
3. Don’t skip doses. Stopping suddenly can cause withdrawal headaches, mood swings, or even seizures.
4. Know the warning signs of a seizure. Muscle twitching, jerking, confusion, staring blankly, or loss of awareness-even for a few seconds-could be a sign. If you notice this, stop the medication and call your doctor immediately.
5. Get your liver checked. If you drink alcohol regularly or have a history of liver problems, ask your doctor for a simple blood test.

Who Should Avoid Bupropion Altogether

Bupropion isn’t for everyone. Avoid it if you:

• Have ever had a seizure
• Have an eating disorder (especially if you’ve lost a lot of weight recently)
• Are going through alcohol or benzodiazepine withdrawal
• Take MAO inhibitors (like phenelzine) within the last 14 days
• Have uncontrolled high blood pressure (above 180/120)

There are other options. If insomnia and anxiety are deal-breakers, sertraline or escitalopram might be better. If weight gain is your concern, bupropion is still a top choice. If sexual side effects ruined your last antidepressant, bupropion might be your best bet. But only if you’re willing to manage the trade-offs.

The Bottom Line

Bupropion is powerful. It helped millions of people feel like themselves again. But it’s not a gentle drug. It’s like a sports car-fast, responsive, and thrilling-but it demands respect. You can’t treat it like a vitamin.

If you’re considering it, ask your doctor: "Am I at risk for seizures? Can we start low and go slow? What’s the plan if I get anxious or can’t sleep?" If you’re already on it, don’t ignore the signs. Insomnia isn’t just annoying-it’s a signal. Anxiety isn’t just stress-it’s your brain reacting. And a seizure isn’t a rare accident-it’s a warning you ignored.

There’s no perfect antidepressant. But there is a right one for you. And that one doesn’t have to come with sleepless nights, panic attacks, or the fear of losing control.