Mounjaro and HRT: Can I Take Them Together?

If you are taking – or thinking about taking – Mounjaro for weight management, you might wonder if it is safe to use it alongside hormone replacement therapy (HRT).

Menopause can also bring concerns like weight gain. So many women want to manage menopause symptoms and explore new treatments for weight control at the same time.

HRT treatments help you manage symptoms by replacing the hormones oestrogen and progestogen. These two hormones decrease as you reach the menopause.

But Mounjaro can also interact with other medicines, changing how they work in the body and potentially worsening existing side effects of Mounjaro. This may include oral HRT. So, let’s look at what current guidance says about using Mounjaro safely when you’re on HRT.

Can You Take HRT and Mounjaro Together?

Yes, you can. However, Mounjaro (tirzepatide) can reduce how well some oral medicines are absorbed. This may include oral HRT tablets. So using both medicines together needs to be done carefully and under medical guidance.

The British Menopause Society (BMS) recommends those who take GLP-1s use transdermal HRT (which delivers hormones through the skin).

This does not mean you cannot take Mounjaro if you are on oral HRT. But you might need to make adjustments to make sure it keeps working properly.

Speak to your GP or menopause specialist for medical advice before you start or change either treatment. They can check your medication, review your symptoms and make sure your HRT continues to work effectively.

Let your Mounjaro provider know you’re using, or thinking of using, oral HRT too.

What HRT Types Are Affected by Mounjaro?

Mounjaro can affect the absorption of oral progestogen, alone or in combined oral HRT (progestogen and oestrogen).

“Mounjaro delays gastric emptying,” Richard Wood, a pharmacist at Simple, explains. “This can reduce absorption of oral medicines, including oral HRT such as oestradiol tablets or Utrogestan.

“Poor absorption of oral progestogen may mean inadequate endometrial protection in women with a uterus.”

Mounjaro does not affect transdermal HRT, which includes patches, gels and sprays. This is because it doesn’t work via the digestive system. It delivers hormones through the skin directly into your bloodstream.

Does Mounjaro Affect the Mirena Coil?

No, Mounjaro doesn’t affect the Mirena coil. In fact, the 52 mg Mirena coil provides the most reliable endometrial protection for women using GLP-1 medicines.

The Mirena coil replaces progestogen, a hormone which decreases during menopause. It releases the hormone directly into the uterus, offering steady protection for up to five years.

It only provides the progestogen element. So you’ll need to take a form of oestrogen alongside the Mirena coil. You can combine it with transdermal oestrogen, like patches, gels or sprays.

How Does Mounjaro Affect Oral HRT?

Mounjaro is a GLP-1 receptor agonist, which works by delaying gastric emptying. This means food and medicines move more slowly from your stomach into your intestines.

This action suppresses your appetite and helps you feel fuller quicker, and for longer. But it can also impact how some medicines are absorbed. This may include oral HRT and oral methods of contraception.

In women with a womb, low absorption of progestogens can unbalance the oestrogen/progesterone ratio. This can lead to lower endometrial protection of the uterus, which increases the risk of endometrial thickening or irregular bleeding. There may also be an increased risk of endometrial cancers. However, the exact risk is currently not well documented.

Common Mounjaro side effects, like diarrhoea and vomiting, can also make oral medicines less effective. If you vomit within two to four hours of taking your pill, your body may not absorb properly the hormones from your HRT.

Mounjaro does not make HRT unsafe, but it can make oral forms less reliable.

According to BMS guidance, GPs should review all women taking oral progestogens who start Mounjaro. Where possible, they suggest switching to a non-oral form to ensure consistent hormone delivery.

Mounjaro and Oral HRT Bleeding: Is It Normal?

Women using oral HRT may notice changes such as irregular bleeding or the return of menopausal symptoms (e.g. hot flushes, mood changes) on Mounjaro. These can be signs that hormone levels have dropped.

Pharmacist Richard Wood says: “Some users report heavier bleeding while using Mounjaro with oral HRT. This is likely due to reduced absorption of oral HRT, not a direct effect of Mounjaro.

“Switching to non-oral HRT or Wegovy usually resolves this issue.”

Taking Oral HRT and Want to Use Mounjaro? Your Options

If you are already taking HRT and want to start Mounjaro (or you are using Mounjaro and thinking about beginning HRT), there is no need to panic. Both treatments can be managed safely together.

Pharmacist Richard Wood says: “You do not have to avoid Mounjaro entirely, but a GP review is essential before starting. This ensures your HRT remains effective and safe.”

Here are some practical options to discuss with your doctor and provider.

Switch to Non-Oral HRT

The BMS recommends patients using GLP-1 treatment use non-oral forms of HRT. Transdermal HRT is also a preferred choice for overweight or obese patients.

Many women also prefer this option because it provides steady hormone levels with fewer ups and downs. It also does not depend on your stomach to work properly.

Transdermal HRT comes in a number of forms, including patches, gels, sprays or vaginal rings, pessaries or creams.

Consider the Mirena Coil

For women with a womb, the Mirena coil provides a replacement for progestogen. You’ll need to combine it with transdermal oestrogen, like sprays, patches and gels.

For many women, combining the Mirena coil with transdermal oestrogen gives an ideal balance. It provides strong endometrial protection, effective symptom relief and Mounjaro won’t impact absorption.

Stay on Oral HRT and Make Adjustments

If you prefer to stay on oral HRT, your GP may advise a temporary increase in progesterone dose for around four weeks after starting Mounjaro or after each dose increase.

However, there is no exact amount defined yet, so this should only be done with your doctor’s supervision.

You should also keep track of your symptoms and report any side effects or changes in bleeding, mood or hot flushes.

Switch to Wegovy

Wegovy (semaglutide) is another GLP-1 medicine used for weight management. However, it does not seem to affect oral HRT absorption in the same way.

Your GP and prescriber can help decide whether switching from Mounjaro to Wegovy might be a better fit for you.

Where to Get Support

Managing menopause symptoms alongside your weight can feel overwhelming. The good news is that safe and effective options exist, and you can get support from both your GP and your provider.

If you are using Mounjaro, you do not need to stop your HRT. You may simply need to change the form or dose to make sure it continues to work properly.

Talking to your GP or a menopause specialist can help you choose an HRT type that suits your lifestyle and health. They can also check your hormone levels and review any bleeding patterns.

Your Mounjaro provider can also provide advice based on your individual needs. They may adjust your treatment or recommend other medications, like Wegovy. If you’re a patient with Simple, get in touch on 0141 774 5023.

Every woman’s body responds differently. The right plan is the one that keeps you feeling well, protected and confident in your treatment choices.

Key Takeaways

• Mounjaro Can Affect Absorption of Oral Medicines: Mounjaro slows stomach emptying. This can reduce how well oral medicines are absorbed. This may include oral progesterone-replacement tablets (and the oral contraceptive pill). Vomiting and diarrhoea, common side effects from GLP-1 agonists, affect absorption too.
• Transdermal HRT is the Safest: Patches, gels and sprays go through the skin straight into the bloodstream. They work normally with Mounjaro and give steady hormone levels.
• Oral HRT May Need Adjusting: Unbalancing your HRT by reducing the absorption of progesterone can lead to Increased risk of: endometrial thickening, irregular bleeding and endometrial cancer. Your GP may suggest increasing the dose temporarily or switching to a non-oral form.
• The Mirena Coil Gives Strong Protection: It releases progestogen directly into the womb, avoiding absorption problems. Combine with an oestrogen patch or gel for full HRT coverage.
• You Don’t Have to Stop Mounjaro or HRT: A GP or menopause review will help tailor your treatment so both work safely. Some women switch to Wegovy if they want to stay on oral HRT.
• Always Check Before Changing Medicines: Tell your doctor if you start Mounjaro, notice bleeding changes, or if your menopause symptoms return. Regular reviews with a healthcare professional will keep your treatment safe and effective.

References

Five Valleys Medical Practice, no date. GLP-1 & progesterone medication update [online]. Available from: https://fivevalleysmedicalpractice.co.uk/medication-updates/glp1-progesterone/ (Accessed: 21 September 2025).

Kim, S.E., Min, J.-S., Lee, S., Lee, D.-Y. & Choi, D., 2023. Different effects of menopausal hormone therapy on non-alcoholic fatty liver disease based on the route of estrogen administration. Scientific Reports [online]. 13, p.15461. Available from: https://doi.org/10.1038/s41598-023-42788-6 (Accessed: 21 September 2025).

Primary Care Women’s Health Society (PCWHS), 2024. Injectable weight loss drugs, contraception and HRT [PDF online]. Authors: Dr. Sarah Gray, Dr. Toni Hazell, Dr. Louise Price & Dr. Lindsey Thomas. Available from: https://www.pcwhs.co.uk/_userfiles/pages/files/resources/glp1_contraception_hrt_article.pdf (Accessed: 21 September 2025).

Shufelt, C.L. & Manson, J.E., 2021. Menopausal hormone therapy and cardiovascular disease: the role of formulation, dose, and route of delivery. Journal of Clinical Endocrinology & Metabolism [online]. 106(5), pp.1245–1254. Available from: https://doi.org/10.1210/clinem/dgab042 (Accessed: 21 September 2025).

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