Drug interactions
Ethinyl estradiol-drospirenone + Felbamate
Severity: Moderate
Ethinyl estradiol-drospirenone and Felbamate: moderate 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
Felbamate is a weak CYP3A4 inducer and has been reported to lower exposure to the ethinyl estradiol and progestin components of hormonal contraceptives. This may reduce contraceptive efficacy and increase the chance of breakthrough bleeding or unintended pregnancy.
What this interaction means in plain words
Ethinyl estradiol-drospirenone and Felbamate can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Ethinyl estradiol-drospirenone belongs to Endocrine; Felbamate belongs to Central Nervous System.
Why it happens
Felbamate induces CYP3A4 metabolism of contraceptive steroids, lowering their plasma concentrations.
What to do
Advise an additional or alternative non-hormonal contraceptive method, or consider a higher-dose or non-oral option, while felbamate is taken. Monitor for breakthrough bleeding as a sign of reduced hormone exposure.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Ethinyl estradiol-drospirenone
- Ethinyl estradiol-drospirenone + Fezolinetant Contraindicated
- Ethinyl estradiol-drospirenone + Ombitasvir / paritaprevir / ritonavir Contraindicated
- Ethinyl estradiol-drospirenone + Ombitasvir / paritaprevir / ritonavir and dasabuvir Contraindicated
- Ethinyl estradiol-drospirenone + Tranexamic acid Contraindicated
- Aminocaproic acid + Ethinyl estradiol-drospirenone Major
- Amobarbital + Ethinyl estradiol-drospirenone Major
Other interactions of Felbamate
- Felbamate + Ulipristal Major
- Amisulpride + Felbamate Moderate
- Amitriptyline + Felbamate Moderate
- Apalutamide + Felbamate Moderate
- Asenapine + Felbamate Moderate
- Bosentan + Felbamate Moderate
Frequently asked questions
Can I take Ethinyl estradiol-drospirenone with Felbamate?
MediHelp rates the interaction as moderate. Ethinyl estradiol-drospirenone and Felbamate can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Felbamate is a weak CYP3A4 inducer and has been reported to lower exposure to the ethinyl estradiol and progestin components of hormonal contraceptives. This may reduce contraceptive efficacy and increase the chance of breakthrough bleeding or unintended pregnancy.
How serious is the interaction between Ethinyl estradiol-drospirenone and Felbamate?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise an additional or alternative non-hormonal contraceptive method, or consider a higher-dose or non-oral option, while felbamate is taken. Monitor for breakthrough bleeding as a sign of reduced hormone exposure.
What other medicines interact with Ethinyl estradiol-drospirenone?
MediHelp also lists interactions of Ethinyl estradiol-drospirenone with, for example, Fezolinetant, Ombitasvir / paritaprevir / ritonavir, Ombitasvir / paritaprevir / ritonavir and dasabuvir. The full list is on the Ethinyl estradiol-drospirenone page.
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