The short explanation
Vomiting or severe diarrhoea can stop the pill from being absorbed properly, so it may not protect you. If you vomit within about three hours of taking a combined pill, or have very severe diarrhoea for more than a day, it is treated like a missed pill. The usual advice is to take another pill if you vomit soon after taking one, continue the pack, and use condoms until you have taken pills normally for seven days after the illness ends. If you had unprotected sex during this time, emergency contraception may be needed. Check your pack leaflet or ask a pharmacist to be sure.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- Some antibiotics and other medicines used for diarrhoea do not usually affect the pill, but certain medicines can. Tell your doctor or pharmacist that you are on the pill.
- Drink plenty of fluids to avoid dehydration.
- If illness continues for several days, see a doctor for both the illness and contraception advice.
- If this happens often, a method not taken by mouth, such as an IUD, implant or injection, may suit you better.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This answer cannot tell exactly how protected you are. A pharmacist or doctor can advise based on your situation.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- Is my pill still working after this illness?
- Do I need emergency contraception?
- How long should I use condoms?
- Will my other medicines affect the pill?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
Get help the same day
- Get care the same day if you cannot keep any fluids down, feel very weak or dizzy, or see blood in stools.
Book an appointment soon
- See a doctor within a few days if diarrhoea or vomiting continues.
Raise it at a routine appointment
- Book a routine appointment if you want to discuss non-oral methods.
Sources
The evidence this explanation is built on.
Who wrote and reviewed this
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- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
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No corrections have been made since this answer was first published.
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