Wellbutrin Side Effects: What's Common and How Long It Lasts
The most common Wellbutrin side effects are dry mouth, nausea, insomnia and feeling on edge, and many ease in the first weeks.
By withClaro Editorial · 2026-11-02 · 4 min read
Clinical section reviewed by Dr. Jason Tan , Consultant Psychiatrist, on October 27, 2026.
Key takeaways In the FDA trials, the most common Wellbutrin side effects were dry mouth, nausea and insomnia, and they grew more common at higher doses. In 100 threads on r/bupropion and r/wellbutrin, feeling anxious, jittery or agitated was the side effect people named most often, followed by insomnia. In the label's trials, sleepiness was as common as on placebo, and more people lost than gained weight. A seizure needs emergency care, and the label says not to restart Wellbutrin after one. Call your prescriber the same day about new thoughts of self-harm or signs of mania. On this page
What are the most common side effects of Wellbutrin? Which side effects do people on r/bupropion name most? How long do Wellbutrin side effects last? Which Wellbutrin side effects are serious? What helps with Wellbutrin side effects? What should you tell your prescriber about Wellbutrin side effects? Wellbutrin (bupropion) works on noradrenaline and dopamine rather than serotonin, so its side effects lean toward the activating kind: trouble sleeping and feeling on edge, rather than sleepiness. Most are more common at higher doses. MedlinePlus lists trouble falling or staying asleep among its common effects.
What are the most common side effects of Wellbutrin?
Dry mouth, nausea and insomnia led the list in the label's depression trials, which compared bupropion sustained-release at 300 mg and 400 mg a day with placebo. Rates at 300 mg, against placebo:
Side effect 300 mg Placebo Dry mouth 17% 7% Nausea 13% 8% Insomnia 11% 6% Constipation 10% 7% Dizziness 7% 5% Tremor 6% 1% Sweating 6% 2% Ringing in the ears 6% 2% Loss of appetite 5% 2%
The dose matters. At 400 mg, insomnia rose to 16%, dizziness to 11% and agitation to 9%, against 11%, 7% and 3% at 300 mg. That is one reason the dose goes up gradually. Sleepiness was about as common as on placebo, at 2%, and weight more often went down: 14% of people on 300 mg lost more than 5 pounds, against 6% on placebo. In the label's trials of immediate-release bupropion, lower sex drive was reported by 3% against 2% on placebo.
Which side effects do people on r/bupropion name most?
Feeling anxious, jittery or agitated. We read 100 recent threads about side effects on r/bupropion and r/wellbutrin, comments included, and 360 people described their own experience. These are people's own accounts, not trial rates, and people with ongoing problems are more likely to post, so treat this as a range of experiences rather than odds. Of the 360, 284 named at least one side effect, 15 said they had none, and the rest didn't say. The table counts the 284 who named one, and one person can be in several rows:
What they named Of 284 people Anxiety, jitteriness or agitation 93 Trouble sleeping 58 Loss of appetite 48 Tiredness 44 Headache 31 Nausea or stomach trouble 29
How long do Wellbutrin side effects last?
For some, within weeks; for about half of those who said, they were still going. Of 90 people on r/bupropion and r/wellbutrin who said how long their side effects lasted, 35 said they eased within weeks and 10 said they lasted months, while 45 were still going when they posted. One person on r/bupropion wrote:
My insomnia problems did resolve around 4 weeks
Bupropion acts from the first dose and reaches steady levels in about 8 days, which is why the activating effects, like insomnia and feeling wired, come early; the change in mood comes later, and MedlinePlus puts the full effect at 4 weeks or longer. Insomnia can last longer if the dose is taken late in the day; MedlinePlus advises not taking it too close to bedtime.
Which Wellbutrin side effects are serious? Medically reviewed by Dr. Jason Tan on October 27, 2026, this section only.
The label warns about seizures, which become more likely at higher doses, and about raised blood pressure, mania and angle-closure glaucoma. In studies of the sustained-release form at up to 300 mg a day, about 1 in 1,000 people had a seizure, and about 4 in 1,000 on the immediate-release form at 300 to 450 mg; the rate for Wellbutrin XL itself was not measured in trials. Never take an extra dose to make up for a missed one, because seizure risk rises with the dose. Bupropion is not prescribed to people with anorexia or bulimia, now or in the past, because seizures were more common in them. The clinical view:
Most early side effects of antidepressants ease within the first weeks, while a few tend to last and are worth raising.
Call your prescriber the same day, or get urgent care, if you notice:
- new or worse thoughts of suicide or self-harm, especially early on, after a dose change, or in people under 25 - a sudden burst of energy, little need for sleep, racing thoughts or unusual risk-taking, especially if you or a close relative has bipolar disorder Wellbutrin has its own warning signs too. Call 911 for a seizure, and do not take another dose: the label says to stop and not restart after one. Get emergency care for eye pain, changes in vision such as colored rings around lights, or redness and swelling around the eye, which MedlinePlus lists as signs of angle-closure glaucoma. A severe headache or pounding heartbeat can mean high blood pressure and needs a call to your prescriber that day.
If you're having thoughts of harming yourself, contact emergency services or a crisis line straight away. In the US, call or text 988. In the UK, call Samaritans on 116 123. Elsewhere, find a crisis line near you .
What helps with Wellbutrin side effects?
Taking the dose in the morning helps most with sleep, and the label gives Wellbutrin XL in the morning. Taking it with food can ease an upset stomach. Keep a short note of each side effect, when it started and whether it is easing, and bring it to your next appointment; more on doses in Wellbutrin dosage .
What should you tell your prescriber about Wellbutrin side effects?
Tell your prescriber which side effects you have, when they started and whether they are easing. That helps them tell an early effect that will pass from one worth changing the dose or medication for. It helps to tell them:
When you started Wellbutrin, your dose and any recent change. Which side effects you have and how strong they are. Whether they’re easing, steady or getting worse. How you sleep, and what time you take your dose. Any other medications, alcohol or caffeine you use. Download on the App Store Side effects on Wellbutrin rise and fade over weeks, and a daily record shows which ones are easing. The withClaro app lets you log mood, sleep, energy and side effects each day, linked to your dose, and turns it into a report for your prescriber.
Frequently asked questions What does Wellbutrin feel like at first? Many people notice more energy, a dry mouth or trouble sleeping in the first weeks, before mood changes. Note what you feel in the first two weeks, so you can tell your prescriber what came first.
Can Wellbutrin make anxiety worse? It can for some people, especially early or after a dose increase. Note whether it started after a dose change and how much caffeine you have, and tell your prescriber if it is hard to bear.
Does Wellbutrin cause hair loss? It wasn't among the common side effects in the trials, but the label lists hair loss among reports after approval, with no known rate. Mention it to your prescriber if you notice it.
When do Wellbutrin side effects mean the dose should change? When they do not ease after a few weeks, get worse after an increase, or get in the way of sleep or work. Note which side effect, since when and at what dose, and bring that to your prescriber rather than changing the dose yourself.
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Sources WELLBUTRIN XL (bupropion) prescribing information, US Food and Drug Administration via DailyMed, revised February 2026 MedlinePlus: Bupropion Claro articles are for self-monitoring and educational purposes only. They are not a medical device, therapist, or diagnostic tool, and do not replace care from your prescribing clinician. If you are in crisis, contact your care team, emergency services, the Samaritans (UK: 116 123), or the Crisis Text Line (US: text HOME to 741741).