herPILL · your contraception guide
The pill and antibiotics — does it still work?
You've probably heard you need condoms whenever you're on antibiotics. For almost all of them, that advice is now out of date. Here's what UK guidance actually says.
Manage your contraceptionThe idea that antibiotics cancel out the pill is one of the most persistent contraception myths in the UK. The reality is far more reassuring — and much simpler once you know the one exception.
The short answer: Most antibiotics do not affect your pill. You can keep taking it as normal, with no need for condoms — unless you're on rifampicin or rifabutin, or you're being sick.
01Why the old advice changed
For years, women were told to use back-up contraception with any antibiotic. After systematically reviewing the evidence, the Faculty of Sexual & Reproductive Healthcare (FSRH) — along with the WHO and the US CDC — concluded that common antibiotics simply don't reduce how well hormonal contraception works. The guidance was updated, but the myth stuck around.
This applies to both the combined pill and the mini pill, as well as the patch and vaginal ring.
02Which antibiotics are fine, and which aren't
✓ No extra precautions needed
- Amoxicillin
- Penicillin
- Trimethoprim (UTIs)
- Doxycycline
- Clarithromycin & erythromycin
- Nitrofurantoin
- Flucloxacillin
The everyday antibiotics for chest, throat, skin, dental and urine infections. Keep taking your pill as normal.
⚠ Extra contraception needed
- Rifampicin
- Rifabutin
These "enzyme-inducing" antibiotics are used mainly for tuberculosis and to prevent meningitis in close contacts. They speed up how your body clears the pill's hormones, so it works less well.
03The real thing to watch: being sick
Here's the part that catches people out. It's usually not the antibiotic itself that's the problem — it's the illness. If you vomit within 2 hours of taking a combined pill, or you have severe diarrhoea, the pill may not be absorbed properly.
- → Vomiting within 2 hours: take another pill straight away, then carry on as normal.
- → Severe diarrhoea: treat each day as a missed-pill day and use condoms until 2 days after you recover.
- → Not sure where you are in the pack? Check our missed-pill guide.
04Quick answers
Does amoxicillin affect the pill?
No. Amoxicillin is one of the common antibiotics that does not reduce the effectiveness of the combined pill or mini pill. Keep taking your pill as normal.
What about the mini pill specifically?
Same rules. The progestogen-only pill is only affected by the enzyme-inducing antibiotics rifampicin and rifabutin — all other common antibiotics are fine.
Do I need condoms while on antibiotics for acne?
Long-term acne antibiotics like doxycycline and lymecycline do not affect the pill, so no extra contraception is needed on their account.
I already used condoms "just in case" — was that wrong?
Not wrong at all — condoms are never a bad idea, and they also protect against STIs. But for common antibiotics, they aren't required to keep the pill working.
Questions about your pill? Ask a pharmacist
A herPILL pharmacist can check any medicine against your contraception and keep you covered — free on the NHS.
Manage your contraceptionSources
- NHS — Will antibiotics stop my contraception working? nhs.uk
- Faculty of Sexual & Reproductive Healthcare (FSRH CEU) — Statement on antibiotics and hormonal contraception; Drug Interactions with Hormonal Contraception.
- patient.info — Which medications can affect your contraception (UK clinical reference).
General information reviewed against current NHS and FSRH guidance, not personal medical advice. If you are prescribed any new medicine, tell the prescriber you use hormonal contraception so interactions can be checked. Always read the patient information leaflet supplied with your medicines.