Drug interactions
Ethinyl estradiol-drospirenone + Tolfenamic acid
Severity: Moderate
Ethinyl estradiol-drospirenone and Tolfenamic acid: 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
NSAIDs such as tolfenamic acid can reduce renal prostaglandin synthesis, which lowers renin and aldosterone and impairs potassium excretion. Combined with drospirenone, which antagonizes aldosterone, this can add to hyperkalemia risk, particularly with renal impairment or long-term NSAID use.
What this interaction means in plain words
Ethinyl estradiol-drospirenone and Tolfenamic acid 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; Tolfenamic acid belongs to Musculoskeletal.
Why it happens
Additive hyperkalemia through NSAID-induced hyporeninemic hypoaldosteronism and drospirenone aldosterone receptor blockade.
What to do
Check serum potassium during the first cycle if long-term daily NSAID use is planned, and monitor in patients with renal impairment. Use the shortest effective NSAID course.
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 Tolfenamic acid
Frequently asked questions
Can I take Ethinyl estradiol-drospirenone with Tolfenamic acid?
MediHelp rates the interaction as moderate. Ethinyl estradiol-drospirenone and Tolfenamic acid 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. NSAIDs such as tolfenamic acid can reduce renal prostaglandin synthesis, which lowers renin and aldosterone and impairs potassium excretion. Combined with drospirenone, which antagonizes aldosterone, this can add to hyperkalemia risk, particularly with renal impairment or long-term NSAID use.
How serious is the interaction between Ethinyl estradiol-drospirenone and Tolfenamic acid?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check serum potassium during the first cycle if long-term daily NSAID use is planned, and monitor in patients with renal impairment. Use the shortest effective NSAID course.
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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