Answer
Fosaprepitant must not be used with pimozide, terfenadine, astemizole or cisapride because its inhibition of CYP3A4 could increase their plasma concentrations, potentially causing serious or life-threatening reactions.
Sources for this answer
- IVEMEND 150 mg powder for solution for infusionMerck Sharp & Dohme (UK) Limited · emc · SmPC §4.5 Interaction with other medicinal products · Version 16Document updated
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