Itraconazole and Methadone: Drug Interaction Guide

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

Interaction severity: Major — avoid combination

How Itraconazole interacts with Methadone

Itraconazole inhibits CYP3A4 metabolism of methadone and both drugs prolong the QT interval, increasing risk of methadone toxicity and torsades de pointes.

What you should do

Obtain ECG before starting, reduce methadone dose, and monitor for sedation, respiratory depression, and QT prolongation.

Key facts

Severity

Major — avoid combination

Mechanism

Itraconazole inhibits CYP3A4 metabolism of methadone and both drugs prolong the QT interval, increasing risk of methadon...

Action

Obtain ECG before starting, reduce methadone dose, and monitor for sedation, respiratory depression, and QT prolongation...

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 Itraconazole and Methadone together?

No — this combination should generally be avoided. Obtain ECG before starting, reduce methadone dose, and monitor for sedation, respiratory depression, and QT prolongation.

What is the severity of this interaction?

The interaction between Itraconazole and Methadone is classified as Major — avoid combination. Itraconazole inhibits CYP3A4 metabolism of methadone and both drugs prolong the QT interval, increasing risk of methadone toxicity and torsades de pointes.

What should I do if I'm prescribed both?

Obtain ECG before starting, reduce methadone dose, and monitor for sedation, respiratory depression, and QT prolongation. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

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