Drug interactions
Amobarbital + Ethinyl estradiol-levonorgestrel
Severity: Major
Amobarbital and Ethinyl estradiol-levonorgestrel: major interaction.
Last updated
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 liver enzymes and lower contraceptive hormone concentrations. This can lead to breakthrough bleeding and contraceptive failure.
What this interaction means in plain words
Amobarbital and Ethinyl estradiol-levonorgestrel 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.
Amobarbital belongs to Central Nervous System; Ethinyl estradiol-levonorgestrel belongs to Endocrine.
Why it happens
Induction of CYP3A4 by amobarbital increases metabolism of ethinyl estradiol and levonorgestrel.
What to do
Use a non-hormonal contraceptive such as a copper IUD instead of relying on the pill during and after barbiturate treatment.
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?
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Other interactions of Ethinyl estradiol-levonorgestrel
- Ethinyl estradiol-levonorgestrel + Fezolinetant Contraindicated
- Ethinyl estradiol-levonorgestrel + Ombitasvir / paritaprevir / ritonavir and dasabuvir Contraindicated
- Ethinyl estradiol-levonorgestrel + Tranexamic acid Contraindicated
- Aminocaproic acid + Ethinyl estradiol-levonorgestrel Major
- Anastrozole + Ethinyl estradiol-levonorgestrel Major
- Antithrombin alfa + Ethinyl estradiol-levonorgestrel Major
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 Ethinyl estradiol-levonorgestrel?
MediHelp rates the interaction as major. Amobarbital and Ethinyl estradiol-levonorgestrel 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 liver enzymes and lower contraceptive hormone concentrations. This can lead to breakthrough bleeding and contraceptive failure.
How serious is the interaction between Amobarbital and Ethinyl estradiol-levonorgestrel?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use a non-hormonal contraceptive such as a copper IUD instead of relying on the pill during and after barbiturate treatment.
What other medicines interact with Ethinyl estradiol-levonorgestrel?
MediHelp also lists interactions of Ethinyl estradiol-levonorgestrel with, for example, Fezolinetant, Ombitasvir / paritaprevir / ritonavir and dasabuvir, Tranexamic acid. The full list is on the Ethinyl estradiol-levonorgestrel page.
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