Quinidine and Sotalol: Drug Interaction Guide

Quick answer: This is a major interaction — avoid combining Quinidine and Sotalol unless specifically directed by your doctor.

Interaction severity: Major — avoid combination

How Quinidine interacts with Sotalol

Both are class III antiarrhythmics (quinidine also class Ia) that prolong the QT interval through potassium channel blockade, causing additive risk of torsades de pointes.

What you should do

Avoid combination. If unavoidable, monitor ECG, correct potassium and magnesium, and discontinue if QTc exceeds 500 ms.

Key facts

Severity

Major — avoid combination

Mechanism

Both are class III antiarrhythmics (quinidine also class Ia) that prolong the QT interval through potassium channel bloc...

Action

Avoid combination. If unavoidable, monitor ECG, correct potassium and magnesium, and discontinue if QTc exceeds 500 ms.

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 Quinidine and Sotalol together?

No — this combination should generally be avoided. Avoid combination. If unavoidable, monitor ECG, correct potassium and magnesium, and discontinue if QTc exceeds 500 ms.

What is the severity of this interaction?

The interaction between Quinidine and Sotalol is classified as Major — avoid combination. Both are class III antiarrhythmics (quinidine also class Ia) that prolong the QT interval through potassium channel blockade, causing additive risk of torsades de pointes.

What should I do if I'm prescribed both?

Avoid combination. If unavoidable, monitor ECG, correct potassium and magnesium, and discontinue if QTc exceeds 500 ms. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

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