Answer
Darifenacin should not be used with ketoconazole because ketoconazole potently inhibits CYP3A4, an enzyme involved in darifenacin metabolism, substantially increasing darifenacin exposure.
Sources for this answer
- Darifenacin 7.5mg prolonged-release tabletsAristo Pharma Limited · emc · SmPC §4.5 Interaction with other medicinal products · Version 2Document updated
Sources checked