Do tirzepatide or semaglutide affect the contraceptive pill?

Why could tirzepatide matter?

Tirzepatide slows stomach emptying, especially after the first dose, and can affect the absorption of some medicines taken by mouth. In a study described in EU Mounjaro information, a single tirzepatide dose changed blood levels of hormones from one combined oral contraceptive. Researchers measured hormone exposure, not pregnancy rates. The finding is specific to the studied preparations and cannot quantify an individual’s risk.3

What do US, UK and EU sources say?

The US Zepbound prescribing information advises people using oral hormonal contraception to switch to a non-oral method or add a barrier method for four weeks after starting Zepbound and for four weeks after each dose increase. UK MHRA public guidance advises people using Mounjaro and an oral pill to add a barrier method for the same periods. EU Mounjaro information reports the measured hormone changes but says no oral-contraceptive dose adjustment is required. These are distinct regulatory assessments, not direct pregnancy-outcome comparisons. Check the current advice for your product and location with a healthcare professional.

If considering a switch, ask when the new method becomes effective and what protection is needed in the meantime; not all methods work immediately.123

What about semaglutide?

Do not assume every medicine in this group has the same interaction. UK NHS Specialist Pharmacy Service guidance says there is no evidence that semaglutide reduces oral contraception effectiveness in the same way; this is not proof that every individual situation is risk-free. Ozempic, Wegovy and Rybelsus are different semaglutide products, with product-specific instructions. Ask about your exact medicine and contraceptive, especially if you have vomiting or diarrhoea.4

Vomiting and diarrhoea are a separate issue

Vomiting or severe diarrhoea can affect absorption of an oral contraceptive, regardless of whether the weight or diabetes medicine has a direct interaction with it. The appropriate missed-pill instructions depend on the contraceptive and circumstances. Check its leaflet and seek prompt pharmacy or clinical advice; if pregnancy protection may have been interrupted, ask promptly whether emergency contraception or other action is relevant. Do not assume a non-oral contraceptive has the same absorption issue as a pill.42

Planning pregnancy or breastfeeding

Contraception, a possible pregnancy and planning pregnancy are related but different questions. Guidance and recommended intervals vary by medicine and jurisdiction. Speak with the prescriber promptly if pregnancy is possible or planned, and discuss treatment decisions rather than making changes based on a general article. See GLP-1 medicines and pregnancy and the tirzepatide and semaglutide profiles.

The UK MHRA advises against using GLP-1 medicines while breastfeeding because there is not enough safety information about possible effects on the baby. If you are breastfeeding or plan to breastfeed, speak with the prescriber about the exact medicine, feeding and treatment options. This is UK guidance; follow the advice of your own care team and local product information.2