Bupropion — Drug Monograph

Brand names: Zyban, Wellbutrin, Wellbutrin SR, Aplenzin

Drug class: Other

Mechanism of Action

An atypical antidepressant that acts as a norepinephrine–dopamine reuptake inhibitor (NDRI). Although its exact cessation pathway is not fully understood, it raises synaptic dopamine and norepinephrine, mimicking some of nicotine's neurochemical effects to reduce withdrawal severity — and it also blunts the weight gain frequently seen during a quit attempt. It is the only non-nicotine, non-varenicline first-line oral option for cessation.

FDA Indications

• Smoking cessation (sustained-release formulation, marketed as Zyban)
• Major depressive disorder and seasonal affective disorder (other formulations)

Common Side Effects

• Insomnia
• Dry mouth
• Headache
• Nausea
• Agitation or anxiety
• Dizziness

Clinical Pearl

Bupropion SR is the go-to cessation drug for patients who also have depression or who are especially concerned about post-quit weight gain, and it can be paired with a nicotine patch. Its defining caution is the seizure threshold — screen for eating disorders, heavy alcohol use, and other seizure risk factors before prescribing.

Related Therapies & Mechanisms

• Varenicline (Chantix) — Other · Tobacco Cessation
• Adagrasib (Krazati) — Other
• Arsenic Trioxide (Trisenox) — Other
• Asparaginase (L-asparaginase, E. coli) (Elspar) — Other