Answer
In healthy adult men, Pegasys (peginterferon alfa-2a) 180 micrograms weekly for 4 weeks increased theophylline AUC by 25% through CYP1A2 inhibition; the interaction is likely maximal after more than 4 weeks, so monitor serum theophylline and adjust its dose appropriately during concomitant use.
Sources for this answer
- Pegasys 90 micrograms, 135 micrograms and 180 micrograms solution for injection in pre-filled syringepharmaand GmbH · emc · SmPC §4.5 Interaction with other medicinal products · Version 2Document updated
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