Drug interactions
Mestranol + Topiramate
Severity: Moderate
Mestranol and Topiramate: 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
Topiramate can lower exposure to the estrogen component of hormonal contraceptives, mainly at higher doses. This may reduce contraceptive efficacy and cause breakthrough bleeding.
What this interaction means in plain words
Mestranol and Topiramate 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.
Why it happens
Topiramate induces CYP3A4 in a dose-dependent manner, increasing the metabolism of the estrogen (mestranol is converted to ethinylestradiol).
What to do
Counsel patients on the possible reduced efficacy at topiramate doses above about 200 mg daily and consider a higher-estrogen product or an additional or alternative non-hormonal contraceptive method. Report breakthrough bleeding.
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 Topiramate
Frequently asked questions
Can I take Mestranol with Topiramate?
MediHelp rates the interaction as moderate. Mestranol and Topiramate 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. Topiramate can lower exposure to the estrogen component of hormonal contraceptives, mainly at higher doses. This may reduce contraceptive efficacy and cause breakthrough bleeding.
How serious is the interaction between Mestranol and Topiramate?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Counsel patients on the possible reduced efficacy at topiramate doses above about 200 mg daily and consider a higher-estrogen product or an additional or alternative non-hormonal contraceptive method. Report breakthrough bleeding.
What other medicines interact with Topiramate?
MediHelp also lists interactions of Topiramate with, for example, Benzhydrocodone / acetaminophen, Buprenorphine long-acting, Buprenorphine subdermal implant. The full list is on the Topiramate page.
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