Drug interactions
Ethinyl estradiol-drospirenone + Warfarin
Severity: Moderate
Ethinyl estradiol-drospirenone and Warfarin: 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
Estrogen-containing contraceptives raise clotting factor levels and can reduce the anticoagulant effect of warfarin, while also increasing baseline thrombotic risk. Warfarin response may therefore be unpredictable.
What this interaction means in plain words
Ethinyl estradiol-drospirenone and Warfarin 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; Warfarin belongs to Cardiovascular.
Why it happens
Estrogen-induced increase in clotting factor synthesis opposes warfarin; mechanism otherwise pharmacodynamic.
What to do
Monitor INR more frequently when starting or stopping the contraceptive and adjust the warfarin dose accordingly. Consider a non-estrogen contraceptive since estrogens are generally avoided in patients needing anticoagulation.
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 Warfarin
- Defibrotide + Warfarin Contraindicated
- Ketorolac + Warfarin Contraindicated
- Abciximab + Warfarin Major
- Acetylsalicylic acid + Warfarin Major
- Adagrasib + Warfarin Major
- Amiodarone + Warfarin Major
Frequently asked questions
Can I take Ethinyl estradiol-drospirenone with Warfarin?
MediHelp rates the interaction as moderate. Ethinyl estradiol-drospirenone and Warfarin 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. Estrogen-containing contraceptives raise clotting factor levels and can reduce the anticoagulant effect of warfarin, while also increasing baseline thrombotic risk. Warfarin response may therefore be unpredictable.
How serious is the interaction between Ethinyl estradiol-drospirenone and Warfarin?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor INR more frequently when starting or stopping the contraceptive and adjust the warfarin dose accordingly. Consider a non-estrogen contraceptive since estrogens are generally avoided in patients needing anticoagulation.
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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