Answer
Balsalazide disodium (Colazide) may raise plasma methotrexate levels because its acetylated metabolites are actively secreted through the same renal tubular route, which matters because methotrexate has a narrow therapeutic range.
Sources for this answer
- Colazide 750mg CapsulesAlmirall Limited · emc · SmPC §4.5 Interaction with other medicinal products · Version 7Document updated
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