Answer
Bone marrow suppression and leucopenia have been reported when oral sulfasalazine is taken with azathioprine or 6-mercaptopurine, due to sulfasalazine's inhibition of thiopurine methyltransferase.
Sources for this answer
- Salazopyrin TabletsPfizer Limited · emc · SmPC §4.5 Interaction with other medicinal products · Version 29Document updated
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