Lantus 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 Lantus (Insulin Glargine). The combination is generally fine at 100 IU/mL, but a small number of medications can reduce contraceptive efficacy meaningfully and need either a backup method or a switch.
How Lantus 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 Insulin Glargine acts on CYP3A4 determines whether Lantus affects contraception. Most agents in Diabetes Treatment have no clinically meaningful effect on the pill at 100 IU/mL.
Practical guidance
According to the prescribing information for Insulin Glargine, women on hormonal contraception should review Lantus 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 Lantus therapy is the standard mitigation.
Frequently asked questions
Will Lantus make my pill less effective? ▾
Most Diabetes Treatment medications at 100 IU/mL do not affect oral contraceptive efficacy. The exceptions are CYP3A4-inducing drugs and a small number of others. The prescribing information for Insulin Glargine states whether the interaction is meaningful.
Do I need a backup contraceptive on Lantus? ▾
Backup contraception is needed only when there is a documented interaction between Lantus and the contraceptive method. For most users at 100 IU/mL, no backup is required. The pharmacist confirms whether Insulin Glargine interacts with hormonal contraception.
More on Lantus
- With alcoholLantus and alcohol — is it safe to drink?
- With foodShould Lantus be taken with food?
- Side effectsLantus side effects: common, rare and warning signs
- Dosage guideLantus dosage guide: how much to take and when
- OnsetHow fast does Lantus start working?
- DurationHow long does Lantus last?
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.