Drug interactions
Amobarbital + Ethinylestradiol
Severity: Major
Amobarbital and Ethinylestradiol: major interaction.
Last updated Sources: Base de donnees publique des medicaments (France)
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.
Summary
Barbiturates induce hepatic enzymes that metabolize estrogens, which can lower ethinylestradiol exposure and reduce the reliability of hormonal contraception. Breakthrough bleeding and unintended pregnancy may occur.
What this interaction means in plain words
Amobarbital and Ethinylestradiol can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Why it happens
Hepatic enzyme induction (including CYP3A4) by amobarbital increases ethinylestradiol clearance.
What to do
Advise a non-hormonal or additional barrier contraceptive method during and for several weeks after amobarbital use. Consider a non-inducing sedative alternative.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Amobarbital and Ethinylestradiol, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
References
Other interactions of Amobarbital
- Amobarbital + Calcium / magnesium / potassium / sodium oxybates Contraindicated
- Amobarbital + Doravirine Contraindicated
- Amobarbital + Elbasvir / grazoprevir Contraindicated
- Amobarbital + Isavuconazonium Contraindicated
- Amobarbital + Isocarboxazid Contraindicated
- Amobarbital + Lonafarnib Contraindicated
Frequently asked questions
Can I take Amobarbital with Ethinylestradiol?
MediHelp rates the interaction as major. Amobarbital and Ethinylestradiol can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Barbiturates induce hepatic enzymes that metabolize estrogens, which can lower ethinylestradiol exposure and reduce the reliability of hormonal contraception. Breakthrough bleeding and unintended pregnancy may occur.
How serious is the interaction between Amobarbital and Ethinylestradiol?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise a non-hormonal or additional barrier contraceptive method during and for several weeks after amobarbital use. Consider a non-inducing sedative alternative.
What other medicines interact with Amobarbital?
MediHelp also lists interactions of Amobarbital with, for example, Calcium / magnesium / potassium / sodium oxybates, Doravirine, Elbasvir / grazoprevir. The full list is on the Amobarbital page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
