Comparative Pharmacology
Head-to-head clinical analysis: WELLBUTRIN versus WELLBUTRIN XL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: WELLBUTRIN versus WELLBUTRIN XL.
WELLBUTRIN vs WELLBUTRIN XL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Bupropion is a relatively selective inhibitor of the neuronal reuptake of norepinephrine and dopamine. It does not inhibit monoamine oxidase or the reuptake of serotonin.
Bupropion is a dopamine and norepinephrine reuptake inhibitor; its mechanism in smoking cessation is unknown.
Immediate-release: 100 mg orally twice daily initially; after 3 days, increase to 100 mg 3 times daily. Sustained-release: 150 mg orally once daily initially; after 3 days, increase to 150 mg twice daily. Extended-release: 150 mg orally once daily initially; after 3 days, increase to 300 mg once daily.
150 mg orally once daily; may increase to 300 mg once daily after 4 days, with maximum 300 mg/day.
None Documented
None Documented
Terminal half-life: 21 ± 6 hours (hydroxybupropion 24 ± 6 h, threohydrobupropion 37 ± 13 h, erythrohydrobupropion 33 ± 10 h); requires 5-8 days to reach steady state
21 ± 9 hours (terminal half-life of bupropion); clinical context: steady-state reached in 5-6 days.
Renal (87% as metabolites, 0.5% unchanged); fecal (10%)
Renal (87% as metabolites, 0.5% as parent drug) and fecal (10%).
Category C
Category C
NDRI Antidepressant
NDRI Antidepressant