Mounjaro (tirzepatide), Contraception and HRT

What You Need to Know

If you’re taking Mounjaro or other GLP-1 (Glucagon Like Peptide 1) medications (like Ozempic or Wegovy), it’s important to understand how they may affect your contraception or hormone replacement therapy (HRT).

Why does it matter?

GLP-1 medications can cause vomiting or diarrhoea, especially when you first start treatment or increase your dose. This can affect how well oral medicines work; including the pill and some types of HRT.

Contraception Advice

If you use oral contraception (like the combined pill or progestogen only pill):

• Vomiting within 2 hours of taking the pill or severe diarrhoea may reduce its effectiveness.
• You may need to use extra protection (like condoms) or switch to a non oral method such as:
  • Contraceptive implant
  • Injection
  • Intrauterine device (IUD or coil)
  • Vaginal ring or patch

If you're unsure, speak to your GP or practice nurse for personalised advice.

Emergency Contraception

If you’ve had unprotected sex and are concerned your pill may not have worked:

• Emergency contraception is available.
• Let your pharmacist or GP know you’re taking a GLP-1 medication.

HRT Considerations

If you’re using oral HRT (tablets):

• Vomiting or diarrhoea may reduce how well it works.
• You may wish to switch to a patch, gel, or spray, which are absorbed through the skin and not affected by stomach upset. 

Talk to Your Healthcare Team

Your GP, nurse, or pharmacist can help you choose the safest and most effective option for your needs. Always let them know if you’re taking Mounjaro or similar medications.

For more information, visit: The College of Sexual and Reproductive Healthcare Website, or speak to your practice team.