Pharmaste Daily: October 8, 2026

Names and formulations

• Wellbutrin XL: once-daily ER product for depression/SAD
• Zyban: recognizable sustained-release smoking-cessation brand; separate indication and directions

Immediate-release, sustained-release, and extended-release products differ in frequency and maximum single-dose rules; verify the formulation and total daily bupropion from all products.

Common use

Wellbutrin XL is labeled for major depressive disorder and prevention of seasonal major depressive episodes; bupropion smoking-cessation products use separate labeling.

Mechanism of action

Inhibits neuronal reuptake of norepinephrine and dopamine without clinically important direct serotonergic activity.

Important adverse effects and monitoring

• Boxed warning: monitor for suicidal thoughts and behavior in children, adolescents, and young adults.
• Seizure risk is dose related; contraindicated with seizure disorders, current or prior bulimia/anorexia nervosa, and abrupt withdrawal from alcohol, benzodiazepines, barbiturates, or antiepileptic drugs.
• Monitor blood pressure, mood activation, agitation, and neuropsychiatric symptoms.

Patient counseling

• Swallow XL tablets whole; do not crush, divide, or chew.
• Take in the morning when prescribed once daily and avoid doubling after a missed dose.

Interaction to recognize

With: CYP2D6 substrates such as metoprolol

Why it matters: Bupropion inhibits CYP2D6 and can increase exposure to susceptible substrates.

Practical response: Monitor the affected medicine and consider dose adjustment when clinically appropriate.

Check the original sources

• DailyMed — Wellbutrin XL (bupropion ER) prescribing information

  Sections: Boxed Warning; 1 Indications and Usage; 2 Dosage and Administration; 4 Contraindications; 5 Warnings and Precautions; 7 Drug Interactions; 12.1 Mechanism of Action; 17 Patient Counseling Information. Source checked 2026-09-13.

Selected learning points; verify current labeling for the complete prescribing information.