Singulair 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 Singulair (Montelukast). The combination is generally fine at 4mg, 5mg, 10mg, but a small number of medications can reduce contraceptive efficacy meaningfully and need either a backup method or a switch.
How Singulair 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 Montelukast acts on CYP3A4 determines whether Singulair affects contraception. Most agents in Respiratory Medications have no clinically meaningful effect on the pill at 4mg, 5mg, 10mg.
Practical guidance
According to the prescribing information for Montelukast, women on hormonal contraception should review Singulair 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 Singulair therapy is the standard mitigation.
Frequently asked questions
Will Singulair make my pill less effective? ▾
Most Respiratory Medications medications at 4mg, 5mg, 10mg do not affect oral contraceptive efficacy. The exceptions are CYP3A4-inducing drugs and a small number of others. The prescribing information for Montelukast states whether the interaction is meaningful.
Do I need a backup contraceptive on Singulair? ▾
Backup contraception is needed only when there is a documented interaction between Singulair and the contraceptive method. For most users at 4mg, 5mg, 10mg, no backup is required. The pharmacist confirms whether Montelukast interacts with hormonal contraception.
More on Singulair
- With alcoholSingulair and alcohol — is it safe to drink?
- With foodShould Singulair be taken with food?
- Side effectsSingulair side effects: common, rare and warning signs
- Dosage guideSingulair dosage guide: how much to take and when
- OnsetHow fast does Singulair start working?
- DurationHow long does Singulair last?
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.