Doxycycline and Rifampicin: Drug Interaction Guide

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

Interaction severity: Moderate — caution required

How Doxycycline interacts with Rifampicin

Rifampicin induces CYP3A4 and other oxidative enzymes that metabolise doxycycline, halving its serum half-life and trough concentrations.

What you should do

Either increase doxycycline to 100 mg twice daily or select an alternative antibiotic when concurrent rifampicin therapy is unavoidable.

Key facts

Severity

Moderate — caution required

Mechanism

Rifampicin induces CYP3A4 and other oxidative enzymes that metabolise doxycycline, halving its serum half-life and troug...

Action

Either increase doxycycline to 100 mg twice daily or select an alternative antibiotic when concurrent rifampicin therapy...

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 Doxycycline and Rifampicin together?

With caution. Either increase doxycycline to 100 mg twice daily or select an alternative antibiotic when concurrent rifampicin therapy is unavoidable.

What is the severity of this interaction?

The interaction between Doxycycline and Rifampicin is classified as Moderate — caution required. Rifampicin induces CYP3A4 and other oxidative enzymes that metabolise doxycycline, halving its serum half-life and trough concentrations.

What should I do if I'm prescribed both?

Either increase doxycycline to 100 mg twice daily or select an alternative antibiotic when concurrent rifampicin therapy is unavoidable. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

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