What are the common side effects of bupropion?

[NOTE: This article has been posted prior to peer review for use in an active research program. This content will be updated with a peer reviewed version as soon as it is available.]

Bupropion is generally well tolerated. According to manufacturer prescribing information, the most common adverse reactions occurring at rates ≥1% more commonly among people taking bupropion than placebo are agitation, dry mouth, constipation, headache/migraine, nausea/vomiting, dizziness, excessive sweating, tremor, insomnia, blurred vision, tachycardia, confusion, rash, hostility, cardiac arrhythmias, and auditory disturbance.^1,2 Exact incidence rates of common and very common adverse events with placebo incidence subtracted are listed below.

Table 1: Common and very common adverse effects and the percentage of their incidence less placebo in manufacturers drug trials for bupropion^1,2

A 1999 combined analysis of three randomized controlled trials of bupropion with doses ranging from 100-400 mg (n=1,372) found that the most common reported adverse events were headache (26.8% bupropion vs 23.4% placebo), dry mouth (16.0% vs 7.0%), nausea (12.5% vs 7.5%), constipation (8.5% vs 6.8%), insomnia (10.5% vs 6.5%), and dizziness (8.3% vs 5.5%).³

A 2003 study examined the incidence of adverse events among 11,735 patients taking bupropion as a smoking cessation aid.⁴ The most commonly reported events were nausea/vomiting (2.97%), dizziness (2.36%), headache/migraine (1.67%), fatigue (1.62%), and depression (1.24%).

Elevated Blood Pressure

Bupropion can increase blood pressure and even precipitate hypertension in patients also using a nicotine transdermal system (NTS).^1,2 A comparative trial of sustained-release bupropion found that 6.1% of participants treated with a combination of bupropion and NTS had treatment-emergent hypertension compared to 2.5% treated with bupropion alone, 1.6% using NTS alone, and 3.1% placebo.

Discontinuation

In clinical trials conducted by manufacturers, 10% of patients discontinued therapy for clinical adverse experiences, namely rash, gastrointestinal disturbances, agitation, and headaches.^1,2

References

1. Wellbutrin (bupropion hydrochloride) tablets [package insert]. Durham, NC: GlaxoSmithKline; 2024.
2. Wellbutrin XL (bupropion hydrochloride extended-release) tablets [package insert]. Bridgewater, NJ: Bausch Health; 2024.
3. Settle EC, Stahl SM, Batey SR, Johnston JA, Ascher JA. Safety profile of sustained-release bupropion in depression: results of three clinical trials. Clin Ther. Mar 1999;21(3):454-63. doi:10.1016/s0149-2918(00)88301-0
4. Boshier A, Wilton LV, Shakir SA. Evaluation of the safety of bupropion (Zyban) for smoking cessation from experience gained in general practice use in England in 2000. Eur J Clin Pharmacol. Dec 2003;59(10):767-73. doi:10.1007/s00228-003-0693-0