Antiviral Medications 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 Antiviral Medications (Antiviral Medications). The combination is generally fine at 200mg, 400mg, 800mg, 30mg, 45mg, but a small number of medications can reduce contraceptive efficacy meaningfully and need either a backup method or a switch.
How Antiviral Medications 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 Acyclovir, Oseltamivir, Valacyclovir acts on CYP3A4 determines whether Antiviral Medications affects contraception. Most agents in Antiviral Medications have no clinically meaningful effect on the pill at 200mg, 400mg, 800mg, 30mg, 45mg.
Practical guidance
According to the prescribing information for Acyclovir, Oseltamivir, Valacyclovir, women on hormonal contraception should review Antiviral Medications 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 Antiviral Medications therapy is the standard mitigation.
Frequently asked questions
Will Antiviral Medications make my pill less effective? ▾
Most Antiviral Medications medications at 200mg, 400mg, 800mg, 30mg, 45mg do not affect oral contraceptive efficacy. The exceptions are CYP3A4-inducing drugs and a small number of others. The prescribing information for Acyclovir, Oseltamivir, Valacyclovir states whether the interaction is meaningful.
Do I need a backup contraceptive on Antiviral Medications? ▾
Backup contraception is needed only when there is a documented interaction between Antiviral Medications and the contraceptive method. For most users at 200mg, 400mg, 800mg, 30mg, 45mg, no backup is required. The pharmacist confirms whether Acyclovir, Oseltamivir, Valacyclovir interacts with hormonal contraception.
Medications in Antiviral Medications
More on Antiviral Medications
- With alcoholAntiviral Medications and alcohol — is it safe to drink?
- With foodShould Antiviral Medications be taken with food?
- Side effectsAntiviral Medications side effects: common, rare and warning signs
- For older adultsAntiviral Medications after 60: doses and safety in older adults
- For womenAntiviral Medications for women: indications and considerations
- For menAntiviral Medications for men: indications and considerations
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.