Carbamazepine and Ethinyl Estradiol: Drug Interaction Guide

Quick answer: This is a major interaction — avoid combining Carbamazepine and Ethinyl Estradiol unless specifically directed by your doctor.

Interaction severity: Major — avoid combination

How Carbamazepine interacts with Ethinyl Estradiol

Carbamazepine induces CYP3A4 and UGT enzymes, increasing metabolism of ethinyl estradiol. This can reduce contraceptive efficacy and cause breakthrough bleeding.

What you should do

Avoid relying on combined hormonal contraception alone. Recommend a non-hormonal or enzyme-inducer-resistant contraceptive method.

Key facts

Severity

Major — avoid combination

Mechanism

Carbamazepine induces CYP3A4 and UGT enzymes, increasing metabolism of ethinyl estradiol. This can reduce contraceptive ...

Action

Avoid relying on combined hormonal contraception alone. Recommend a non-hormonal or enzyme-inducer-resistant contracepti...

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 Carbamazepine and Ethinyl Estradiol together?

No — this combination should generally be avoided. Avoid relying on combined hormonal contraception alone. Recommend a non-hormonal or enzyme-inducer-resistant contraceptive method.

What is the severity of this interaction?

The interaction between Carbamazepine and Ethinyl Estradiol is classified as Major — avoid combination. Carbamazepine induces CYP3A4 and UGT enzymes, increasing metabolism of ethinyl estradiol. This can reduce contraceptive efficacy and cause breakthrough bleeding.

What should I do if I'm prescribed both?

Avoid relying on combined hormonal contraception alone. Recommend a non-hormonal or enzyme-inducer-resistant contraceptive method. Always consult your prescribing clinician — do not stop or change medications without medical guidance.

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