Progestin
Medroxyprogesterone 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 Medroxyprogesterone (Medroxyprogesterone). The combination is generally fine at 2.5mg, 5mg, 10mg, but a small number of medications can reduce contraceptive efficacy meaningfully and need either a backup method or a switch.
How Medroxyprogesterone 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 Medroxyprogesterone acts on CYP3A4 determines whether Medroxyprogesterone affects contraception. Most agents in Progestin have no clinically meaningful effect on the pill at 2.5mg, 5mg, 10mg.
Practical guidance
According to the prescribing information for Medroxyprogesterone, women on hormonal contraception should review Medroxyprogesterone 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 Medroxyprogesterone therapy is the standard mitigation.
Frequently asked questions
Will Medroxyprogesterone make my pill less effective? ▾
Most Progestin medications at 2.5mg, 5mg, 10mg do not affect oral contraceptive efficacy. The exceptions are CYP3A4-inducing drugs and a small number of others. The prescribing information for Medroxyprogesterone states whether the interaction is meaningful.
Do I need a backup contraceptive on Medroxyprogesterone? ▾
Backup contraception is needed only when there is a documented interaction between Medroxyprogesterone and the contraceptive method. For most users at 2.5mg, 5mg, 10mg, no backup is required. The pharmacist confirms whether Medroxyprogesterone interacts with hormonal contraception.
Products containing Medroxyprogesterone
More on Medroxyprogesterone
- With alcoholMedroxyprogesterone and alcohol — is it safe to drink?
- With foodShould Medroxyprogesterone be taken with food?
- Side effectsMedroxyprogesterone side effects: common, rare and warning signs
- Dosage guideMedroxyprogesterone dosage guide: how much to take and when
- OnsetHow fast does Medroxyprogesterone start working?
- DurationHow long does Medroxyprogesterone last?
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.