Answer
Combining azathioprine with ribavirin is not advised because severe myelosuppression has been reported with co-administration; ribavirin inhibits inosine monophosphate dehydrogenase, reducing production of active 6-thioguanine nucleotides.
Sources for this answer
- Azathioprine 50mg Film-Coated TabletsTillomed Laboratories Ltd · emc · SmPC §4.5 Interaction with other medicinal products · Version 9Document updated
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