Answer
Taking tolterodine tartrate with systemic clarithromycin is not recommended because clarithromycin is a potent CYP3A4 inhibitor that can increase serum tolterodine concentrations in poor CYP2D6 metabolisers, creating a risk of overdose.
Sources for this answer
- Detrusitol XL 4 mg Prolonged-release CapsulesViatris (formerly Mylan or Upjohn) · emc · SmPC §4.5 Interaction with other medicinal products · Version 23Document updated
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