Drug interactions
Fosfomycin + Mestranol
Severity: Minor
Fosfomycin and Mestranol: minor 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
Mestranol is the estrogen component of some oral contraceptives, and antibiotics have been theorized to lower estrogen levels via gut flora changes. Evidence of contraceptive failure with non-rifamycin antibiotics is weak and fosfomycin is not an established cause.
What this interaction means in plain words
Fosfomycin and Mestranol have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Theoretical reduction in enterohepatic recirculation of ethinyl-type estrogens due to altered intestinal flora.
What to do
No additional contraception is routinely required. Reinforce adherence and advise backup contraception if vomiting or severe diarrhea occurs.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Fosfomycin
- Cholera vaccine + Fosfomycin Moderate
- Fosfomycin + Metoclopramide Moderate
- Fosfomycin + Metoclopramide intranasal Moderate
- Fosfomycin + Microbiota Moderate
- Fosfomycin + Typhoid vaccine live Moderate
- Bazedoxifene / conjugated estrogens + Fosfomycin Minor
Frequently asked questions
Can I take Fosfomycin with Mestranol?
MediHelp rates the interaction as minor. Fosfomycin and Mestranol have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Mestranol is the estrogen component of some oral contraceptives, and antibiotics have been theorized to lower estrogen levels via gut flora changes. Evidence of contraceptive failure with non-rifamycin antibiotics is weak and fosfomycin is not an established cause.
How serious is the interaction between Fosfomycin and Mestranol?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: No additional contraception is routinely required. Reinforce adherence and advise backup contraception if vomiting or severe diarrhea occurs.
What other medicines interact with Fosfomycin?
MediHelp also lists interactions of Fosfomycin with, for example, Cholera vaccine, Metoclopramide, Metoclopramide intranasal. The full list is on the Fosfomycin page.
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