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