If you are taking GLP-1 weight loss medications like Mounjaro or Wegovy, it’s important to use reliable contraception — especially if you are sexually active and could become pregnant.
💊 Using the Pill
- Mounjaro (tirzepatide): May reduce pill absorption. You should use condoms as backup for 4 weeks after starting or increasing your dose.
- Wegovy (semaglutide): No known interaction with oral contraceptives, unless you experience severe diarrhoea or vomiting.
🚨 Vomiting or Diarrhoea
These common side effects can affect the absorption of your pill. If vomiting occurs within 3 hours of taking the pill, or if you have severe diarrhoea for more than 24 hours, follow missed pill guidance and use additional protection.
🩺 Non-Oral Contraception
There’s no evidence that GLP-1 medications affect methods like the coil, implant, injection, patch, or ring — these can be used safely without extra precautions.
🔄 Switching to Mounjaro?
If switching to Mounjaro from another GLP-1 medication, you should use a barrier method for 4 weeks after switching and 4 weeks after any dose increase.
If you’re unsure which contraceptive method is best for you while on weight loss treatment, please speak to our clinical team or your GP for tailored advice.
Source: Faculty of Sexual and Reproductive Healthcare (FSRH)