Answer
Bupropion hydrochloride inhibits CYP2D6, the enzyme required for tamoxifen's metabolic activation, so taking them together may reduce tamoxifen's effectiveness.
Sources for this answer
- Zyban 150 mg prolonged release tabletsGlaxoSmithKline UK · emc · SmPC §4.5 Interaction with other medicinal products · Version 47Document updated
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