Ethinylestradiol and Lamotrigine: Drug Interaction Guide
Quick answer: This combination requires caution. Ethinylestradiol and Lamotrigine can be used together with adjustments and monitoring.
How Ethinylestradiol interacts with Lamotrigine
Ethinylestradiol induces UGT1A4-mediated glucuronidation of lamotrigine, reducing lamotrigine plasma levels by approximately 50% during active pill phase and risking seizure breakthrough.
What you should do
Increase lamotrigine dose during active pill weeks or use continuous (no pill-free week) regimen; monitor for seizures and rash if discontinuing the contraceptive.
Key facts
Severity
Moderate — caution required
Mechanism
Ethinylestradiol induces UGT1A4-mediated glucuronidation of lamotrigine, reducing lamotrigine plasma levels by approxima...
Action
Increase lamotrigine dose during active pill weeks or use continuous (no pill-free week) regimen; monitor for seizures a...
Frequently asked questions
Can I take Ethinylestradiol and Lamotrigine together?
With caution. Increase lamotrigine dose during active pill weeks or use continuous (no pill-free week) regimen; monitor for seizures and rash if discontinuing the contraceptive.
What is the severity of this interaction?
The interaction between Ethinylestradiol and Lamotrigine is classified as Moderate — caution required. Ethinylestradiol induces UGT1A4-mediated glucuronidation of lamotrigine, reducing lamotrigine plasma levels by approximately 50% during active pill phase and risking seizure breakthrough.
What should I do if I'm prescribed both?
Increase lamotrigine dose during active pill weeks or use continuous (no pill-free week) regimen; monitor for seizures and rash if discontinuing the contraceptive. Always consult your prescribing clinician — do not stop or change medications without medical guidance.
Last reviewed: by iMedic Medical Editorial Team. Our editorial process.