Neuraminidase inhibitor
Oseltamivir with the birth control pill
Many women of reproductive age take a combined or progestogen-only oral contraceptive while also using a chronic medication such as Oseltamivir (Oseltamivir). The combination is generally fine at 30mg, 45mg, 75mg, but a small number of medications can reduce contraceptive efficacy meaningfully and need either a backup method or a switch.
How Oseltamivir can affect contraceptive efficacy
Combined and progestogen-only contraceptives are metabolised through CYP3A4. Strong CYP3A4 inducers (some antiepileptics, rifampicin, St John's Wort) lower contraceptive plasma levels and reduce efficacy. Whether Oseltamivir acts on CYP3A4 determines whether Oseltamivir affects contraception. Most agents in Neuraminidase inhibitor have no clinically meaningful effect on the pill at 30mg, 45mg, 75mg.
Practical guidance
According to the prescribing information for Oseltamivir, women on hormonal contraception should review Oseltamivir with the prescribing pharmacist or doctor. Where an interaction is documented, additional barrier contraception or switching to a non-oral method (IUD, implant) for the duration of Oseltamivir therapy is the standard mitigation.
Frequently asked questions
Will Oseltamivir make my pill less effective? ▾
Most Neuraminidase inhibitor medications at 30mg, 45mg, 75mg do not affect oral contraceptive efficacy. The exceptions are CYP3A4-inducing drugs and a small number of others. The prescribing information for Oseltamivir states whether the interaction is meaningful.
Do I need a backup contraceptive on Oseltamivir? ▾
Backup contraception is needed only when there is a documented interaction between Oseltamivir and the contraceptive method. For most users at 30mg, 45mg, 75mg, no backup is required. The pharmacist confirms whether Oseltamivir interacts with hormonal contraception.
Products containing Oseltamivir
More on Oseltamivir
- With alcoholOseltamivir and alcohol — is it safe to drink?
- With foodShould Oseltamivir be taken with food?
- Side effectsOseltamivir side effects: common, rare and warning signs
- Dosage guideOseltamivir dosage guide: how much to take and when
- OnsetHow fast does Oseltamivir start working?
- DurationHow long does Oseltamivir last?
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.