Sulfasalazine and Warfarin: Drug Interaction Guide

Quick answer: This combination requires caution. Sulfasalazine and Warfarin can be used together with adjustments and monitoring.

Interaction severity: Moderate — caution required

How Sulfasalazine interacts with Warfarin

Sulfasalazine displaces warfarin from plasma proteins and may inhibit CYP2C9 metabolism, increasing free warfarin and INR.

What you should do

Monitor INR within 3-5 days of initiating or discontinuing sulfasalazine and adjust warfarin dose; alert patients to signs of bleeding.

Key facts

Severity

Moderate — caution required

Mechanism

Sulfasalazine displaces warfarin from plasma proteins and may inhibit CYP2C9 metabolism, increasing free warfarin and IN...

Action

Monitor INR within 3-5 days of initiating or discontinuing sulfasalazine and adjust warfarin dose; alert patients to sig...

Important medical disclaimer: This page provides educational information about drug interactions for general reference. It is not a substitute for professional medical advice, diagnosis, or treatment. Always discuss your specific medications with a qualified healthcare provider before starting, stopping, or changing any treatment. About our editorial team.

Frequently asked questions

Can I take Sulfasalazine and Warfarin together?

With caution. Monitor INR within 3-5 days of initiating or discontinuing sulfasalazine and adjust warfarin dose; alert patients to signs of bleeding.

What is the severity of this interaction?

The interaction between Sulfasalazine and Warfarin is classified as Moderate — caution required. Sulfasalazine displaces warfarin from plasma proteins and may inhibit CYP2C9 metabolism, increasing free warfarin and INR.

What should I do if I'm prescribed both?

Monitor INR within 3-5 days of initiating or discontinuing sulfasalazine and adjust warfarin dose; alert patients to signs of bleeding. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

Last reviewed: by iMedic Medical Editorial Team. Our editorial process.