Drug interactions
carbamazepine + ethinyl estradiol/levonorgestrel
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Overview
↓ contraceptive effectiveness; breakthrough bleeding.
Mechanism of action
CYP3A induction by CBZ.
Clinical management
Use higher-dose estrogen or non-hormonal method.
Drug reference
References
- Enzyme inducers and COCs — SPS
- CBZ reduces OCP levels — PubMed
Frequently asked questions
Can I take carbamazepine with ethinyl estradiol/levonorgestrel?
The interaction is rated: Major. ↓ contraceptive effectiveness; breakthrough bleeding.
How serious is the interaction between carbamazepine and ethinyl estradiol/levonorgestrel?
The interaction is rated: Major. Evidence level: High.
How is the interaction between carbamazepine and ethinyl estradiol/levonorgestrel managed?
Use higher-dose estrogen or non-hormonal method.
Why do carbamazepine and ethinyl estradiol/levonorgestrel interact?
CYP3A induction by CBZ.
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