Introduction
Medicines such as Wegovy (semaglutide) and Mounjaro (tirzepatide) are increasingly used to help with weight loss and blood-sugar control. Many women taking these treatments are also using hormone replacement therapy (HRT) to manage symptoms of perimenopause or menopause.
Because GLP-1 medicines slow how quickly the stomach empties, they can affect the absorption of oral hormones such as oestrogen or progestogen. Understanding this helps ensure your HRT remains both safe and effective.
How GLP-1 Medicines Affect HRT
GLP-1 medicines delay gastric emptying, which can make absorption of oral tablets slower or less predictable (1). This may reduce the amount of hormone absorbed from oral HRT tablets, particularly during the first few weeks of weight loss treatment or after a dose increase (2).
Non-oral options such as patches, gels, vaginal tablets, or intrauterine systems (IUS) are not affected because they bypass the digestive system (3).
What the Guidelines Say
British Menopause Society (BMS, 2025):
The BMS advises that transdermal oestrogen (patch or gel) is preferred for women using GLP-1 medicines, especially those with obesity or diabetes (4).
GLP-1 treatment may also reduce absorption of oral progestogens such as norethisterone or medroxyprogesterone (4).
If oral HRT is continued, your prescriber may consider a temporary increase in progestogen dose for four weeks after starting or increasing the GLP-1 dose. They will advise you to watch out for unscheduled or breakthrough bleeding, which can suggest hormone fluctuations (5).
Primary Care Women’s Health Forum (PCWHS, April 2025):
The PCWHS confirms that HRT can be used safely alongside GLP-1s if appropriate formulations are chosen (6). Women should be aware that nausea or vomiting may reduce the absorption of oral hormones. Non-oral routes are therefore generally preferred.
What Patients Should Consider
1.Starting Treatment
Tell your GP or menopause specialist before starting weight loss injections, if you are using HRT.
If taking oral oestrogen ask about switching to transdermal oestrogen (patch or gel). If you take an oral progestogen, your clinician may adjust the dose initially or switch the formulation.
2. During treatment / Maintenance
- Report new or prolonged vaginal bleeding, especially within the first few months.
- If you experience severe nausea, vomiting, or diarrhoea, absorption of oral HRT may be reduced - in this case, please inform your prescriber.
- Attend regular menopause reviews, especially when your GLP-1 dose changes.
3. Discontinuation of treatment after weight loss
Weight loss can alter hormone metabolism, so your HRT dose may need review.
Continue using the lowest effective dose that controls your symptoms.
4. Lifestyle Tips for Menopause and Weight Loss
- Balanced diet: Eat plenty of vegetables, wholegrains, lean protein, and calcium-rich foods for bone health.
- Regular exercise: Combine cardio with strength training to support bone and heart health.
- Avoid smoking and limit alcohol: Both worsen hot flushes and raise cardiovascular risk.
- Prioritise sleep and stress management: Mindfulness, yoga, or relaxation can improve mood and energy.
When to seek medical advice urgently:
- Heavy unscheduled vaginal bleeding
- New breast lumps or nipple changes
- Persistent nausea, vomiting, or abdominal pain
- Chest pain, dizziness, or shortness of breath
If symptoms are severe, call 999 or go to A&E.
Summary
GLP-1 medicines and HRT can be used together safely, but oral hormone tablets may be absorbed less effectively due to slower stomach emptying.
To stay safe:
- Prefer transdermal (patch or gel) or non-oral HRT forms.
- Report any unscheduled bleeding or persistent side-effects.
- Keep your GP or menopause specialist informed about medication changes.
With proper monitoring, GLP-1 medicines and HRT can work together to support both metabolic and menopausal health.
References
- Drucker DJ. The cardiovascular biology of glucagon-like peptide-1. Cell Metab. 2016;24(1):15–30.
- Nauck MA, Quast DR, Wefers J, Meier JJ. GLP-1 receptor agonists in the treatment of type 2 diabetes – state-of-the-art. Mol Metab. 2021;46:101102.
- Faculty of Sexual and Reproductive Healthcare (FSRH). Combined hormonal contraception. Oct 2023.
- British Menopause Society (BMS). Use of incretin-based therapies (GLP-1 agonists) in women using HRT. Apr 2025.
- BMS. Management of unscheduled bleeding on HRT. Apr 2024.
- Primary Care Women’s Health Forum (PCWHS). Injectable weight loss drugs, contraception and HRT. Apr 2025.