Important advice when taking Contraceptive or HRT and using Mounjaro.
Posted on 27th May, 2025
Please read the information below carefully if you are using both Mounjaro and a Contraceptive or HRT. If you feel this applies to you or would like to discuss further, please contact the surgery.
I am taking the pill. Will using a GLP-1 agonist affect my contraception?
This depends on the type of GLP-1 agonist that you are using.
If you are using tirzepatide (Mounjaro), you should use condoms along with your pill for four weeks after you start the medicine and for four weeks after any dose increase. This is because tirzepatide works a bit differently from other similar medicines. You might also think about using a different type of contraception that isn’t a pill while on tirzepatide.
For other medicines like semaglutide, exenatide, liraglutide, dulaglutide, or lixisenatide, there is no proof that they make the pill less effective
I have diarrhoea and vomiting with my GLP-1 agonist, and I take the contraceptive pill, what should I do?
Diarrhoea and vomiting can happen when taking GLP-1 agonists and might make the pill less effective. If you vomit within three hours of taking your pill, or have bad diarrhoea for more than a day, follow the guidance for missed pills. If diarrhoea or vomiting continues, think about using a different type of contraception that isn’t a pill, or use condoms as well.
I’m on HRT and taking Mounjaro – what do I need to know?
If you are taking oral progestogen as part of your HRT (for example Utrogestan, Norethisterone, Medroxyprogesterone), then you need to be aware that tirzepatide (Mounjaro) may have an impact on the effectiveness of your HRT. This means your HRT might not protect your endometrium (womb lining) enough. Please contact the surgery to book an HRT review, as we may need to increase your dose or change you to a different form of medication.
If you do not take your HRT orally (for example, you use a patch, a gel or a Mirena coil instead of a tablet) then you do not need to worry.