THE SHORT VERSION
- Wegovy's current leaflet says it should not be used while breastfeeding.
- Mounjaro's updated leaflet advises discussing use or continuation with your doctor.
Understand the current difference
Wegovy's UK leaflet says not to use it while breastfeeding. Mounjaro's September 2026 leaflet reports very low transfer into breast milk and asks you to speak to your doctor before starting or continuing. Its professional information says use could be considered.
Mounjaro's evidence includes a small single-dose study, not proof of safety in every situation. Effects of reduced maternal food intake on milk nutrition remain uncertain. Older MHRA general guidance still advises avoiding GLP-1 medicines while breastfeeding; ask your clinician to reconcile the current sources for you.
Discuss feeding and treatment priorities together
Tell the clinician your baby's age, whether they were premature, how feeding is going and why you need treatment. Include other medicines and any difficulty eating enough yourself.
Ask about alternatives, specialist advice and what would be monitored. Do not assume timing an injection around a feed resolves the uncertainty. If you have already used a medicine, share the dates and arrange advice; avoid an abrupt feeding decision based only on a website.
Sources you can check
- Mounjaro KwikPen: current UK patient leaflet
- Mounjaro: UK product information and lactation evidence
- Wegovy FlexTouch: current UK patient leaflet
- MHRA: GLP-1 medicines safety guidance
Editorial presentation updated 24 October 2026. This is general information, not individual medical advice or a claim of independent clinical review. Read the linked source and the leaflet supplied with your medicine for the full context. Suggest a correction.