Can you take peptides while on HRT (menopausal hormone therapy)?

The short answer

Evidence tier: 3 — mostly observational human data for GLP-1s, mechanistic human data for GH peptides, no combination data for the rest.

Little research has looked at peptides and menopausal hormone therapy (MHT/HRT) together. The main exception is GLP-1 drugs. Observational studies from Mayo Clinic found that postmenopausal women on MHT lost more weight on semaglutide, and one small study found the same for tirzepatide. None of these studies was randomized, so they can't show that MHT caused the extra weight loss.

For growth-hormone-releasing peptides, the evidence is indirect but solid. Oral estrogen lowers IGF-1. Transdermal estrogen does not. So the route of your estrogen may change how your body responds to anything that works through the GH/IGF-1 axis. Nobody has studied tesamorelin or sermorelin in women on HRT.

For PT-141, kisspeptin and topical GHK-Cu, we found no studies of them combined with HRT. That doesn't show they're unsafe together. It means nobody has checked.

The key points:

• Semaglutide + MHT: two retrospective Mayo Clinic analyses found more weight loss in women on MHT. The Spanish Menopause Society calls this hypothesis-generating. It isn't a reason to start HRT.
• Tirzepatide + oral hormones: tirzepatide slows stomach emptying and lowers oral contraceptive absorption. Lilly says oral HRT with tirzepatide has not been studied.
• GH peptides: oral estrogen lowers IGF-1. GH-deficient women on oral estrogen needed about twice the growth hormone dose to reach the same IGF-1 level in one clinical study.
• PT-141 (Vyleesi) is FDA-approved only for premenopausal women. Its label states it is not indicated after menopause.
• Teriparatide, a prescription peptide, has the clearest randomized data with HRT, for osteoporosis.

Do GLP-1 drugs work differently in women on HRT?

Evidence tier: 3 — retrospective cohort studies and conference data. No randomized trial has tested MHT against no MHT in GLP-1 users.

Three Mayo Clinic analyses point the same way:

• *Semaglutide, 2024 (Menopause). 106 postmenopausal women; 16 were on hormone therapy. At 12 months, women on HT had lost about 16% of body weight, against 12%* for non-users (Hurtado et al.). The HT group was very small.
• Tirzepatide, ENDO 2025. 120 women, propensity-matched. At last follow-up, mean weight loss was 19.2% with MHT vs 14.0% without (Healio report). Only 40 women were in the MHT arm.
• Larger cohort, Menopause Society 2026. More than 3,800 women from a multi-site health-record database. Semaglutide users on MHT kept a modest edge (11.9% vs 10.9% at last follow-up). For tirzepatide, the gap was significant only at 3 months (Patient Care report). This was a conference presentation and has not yet appeared in a journal.

The authors themselves name the main problem: healthy-user bias. Women who get prescribed HRT may differ in health, access to care and follow-up in ways that also affect weight loss. In 2026 the Spanish Menopause Society concluded that the MHT–semaglutide link "remains hypothesis-generating and should not justify initiating hormone therapy solely to augment weight loss" (Sánchez-Prieto et al.).

In the trials themselves, menopause doesn't seem to blunt the effect. A post hoc analysis of the SURMOUNT trials found similar tirzepatide weight loss in premenopausal (26%), perimenopausal (23%) and postmenopausal (23%) women (Tchang et al.). That analysis did not separate out HRT use.

Can GLP-1s affect absorption of oral HRT?

There's no direct data. There are relevant labels and drug-interaction studies:

• Tirzepatide: the Zepbound label tells users of oral contraceptives to switch to a non-oral method, or add a barrier method, for 4 weeks after starting and after each dose increase. Lilly's medical information states there is "no information on the use of tirzepatide in people taking oral hormonal replacement therapy" (Lilly Medical).
• Semaglutide: in a study of postmenopausal women with type 2 diabetes, semaglutide did not reduce absorption of a combined oral contraceptive (Kapitza et al.).
• Vomiting and diarrhoea from either drug could reduce absorption of any oral hormone. UK sexual-health guidance (FSRH) makes this point for the pill (FSRH CEU).

HRT doses and goals differ from contraception. Patches, gels, sprays and the hormonal IUD don't pass through the stomach. Whether an oral progestogen still protects the womb lining during tirzepatide dose increases has not been studied. That makes it a reasonable question to ask your prescriber.

Does HRT change how GH-releasing peptides work?

Evidence tier: 2 — small randomized and prospective human studies on estrogen route and the GH/IGF-1 axis. No studies of GH peptides in women on HRT.

The liver makes most circulating IGF-1. Oral estrogen reaches the liver at high concentration on its first pass, and that suppresses IGF-1 production. Estrogen through the skin bypasses this effect.

• In postmenopausal women, oral ethinyl estradiol raised GH but lowered IGF-1. Transdermal estradiol raised IGF-1 to near premenopausal levels (Weissberger et al. 1991).
• A year-long randomized trial found lower IGF-1 with oral estradiol than with intranasal estradiol, even though intranasal reached blood estrogen levels high enough that IGF-1 suppression had been predicted. The authors concluded the effect depends on route, not dose (Davis et al. 2008).
• In GH-deficient adults, women on oral estrogen needed about 867 µg/day of GH, against 424 µg/day for women not on oral estrogen, to reach similar IGF-1 levels (Cook et al. 1999).

What this means for peptides. Tesamorelin and sermorelin are GHRH analogues. Ipamorelin and MK-677 act on the ghrelin receptor. All of them work by raising GH, and much of GH's effect runs through IGF-1. It's plausible that a woman on oral estrogen sees a smaller IGF-1 rise than one on a patch. Nobody has tested this. We found no published study of any GH-releasing peptide in women taking HRT.

Other relevant facts:

• Tesamorelin (Egrifta) is FDA-approved only for excess belly fat in people with HIV lipodystrophy. Trial participants were roughly 84–86% men. The label says GH may change the clearance of drugs processed by CYP450 enzymes, including sex steroids. It also requires IGF-1 monitoring (FDA label). In the EU, the application was withdrawn in 2012 while regulators still had concerns, including rising IGF-1 (EMA).
• Sermorelin: in a small 1997 trial of a GHRH analogue in adults aged 55–71, IGF-1 rose in both sexes. Gains in lean mass, insulin sensitivity and wellbeing appeared in men but not women, and bone density didn't change (Khorram et al.). HRT use wasn't reported.

What about PT-141 or kisspeptin with HRT?

Evidence tier: 3 — label data for PT-141. One small physiology study of kisspeptin in postmenopausal women with and without estradiol.

PT-141 (bremelanotide, Vyleesi) was approved after trials in premenopausal women with an average age of 39 (Kingsberg et al.). The label states it is not indicated for postmenopausal women (Vyleesi label). Its interaction section doesn't mention hormones. It does say bremelanotide may slow stomach emptying and reduce absorption of oral drugs. It also notes a temporary blood pressure rise after each dose and lists uncontrolled hypertension and known cardiovascular disease as contraindications. Those points matter for any woman weighing HRT and cardiovascular risk with her doctor.

Kisspeptin is the one peptide here with direct data on how estradiol changes its effect. In postmenopausal women, a continuous kisspeptin infusion did little to LH at first. In women given estradiol, LH pulses grew in proportion to estradiol levels (Lippincott et al. 2017). So HRT may change how the body responds to kisspeptin. That was a small infusion study of 8 women, not a treatment trial. Kisspeptin's sexual-desire research has been in premenopausal women (Thurston et al. 2022). It is not an approved treatment anywhere.

Testosterone is used off-label (or under local licences) for low desire after menopause (Global Consensus). We found no studies of it combined with PT-141 or kisspeptin.

Is topical GHK-Cu a concern with HRT?

Evidence tier: 4 — no combination studies. Reasoning from mechanism only.

We found no study of copper peptide skincare in women on HRT, and no proposed way the two would interact. GHK-Cu research centres on skin repair and gene expression (Pickart & Margolina 2018), not on sex hormones. The safety questions for injectable GHK-Cu are separate. The FDA plans to consult its advisory committee on injectable GHK-Cu at a meeting expected before February 2027 (Goodwin). People with Wilson's disease have their own copper-related contraindication.

Which combinations have the most and least data?

Evidence tier: varies by row — see the table.

The teriparatide row comes from two small randomized trials in women already on HRT. Adding daily PTH(1-34) raised spine bone density by about 13% (Lindsay et al. 1997; Cosman et al. 2001). Our bone density article covers this.

What should you tell your prescriber?

Evidence tier: 1 — guidelines say HRT decisions should be individualized by type, dose, route and timing. The checklist itself is editorial.

The Menopause Society's position statement says HRT's risks and benefits depend on type, dose, duration, route of administration and timing (NAMS 2022). Your prescriber can only weigh those properly with the full picture. Tell them:

1. The exact HRT you use. Include the estrogen route (oral, patch, gel, spray, vaginal), the progestogen type and route, and any testosterone.
2. Every peptide, including compounded, "research-grade" or overseas products, with the dose and how often you take it.
3. When you start or raise a GLP-1 dose. This matters most if any of your hormones are oral and if you have vomiting or diarrhoea.
4. Any planned GH-axis peptide. Ask whether an IGF-1 baseline and follow-up test makes sense, and how your estrogen route may affect the result.
5. New bleeding, blood pressure changes or headaches after adding anything.
6. Bone and muscle goals. This matters if you're losing weight on a GLP-1 after menopause.

Our labs guide explains common baseline tests.

Limitations of the evidence

Evidence tier: — summary of the evidence gaps above.

• The GLP-1 findings come from retrospective cohorts and conference data. None was randomized, and healthy-user bias can't be ruled out.
• The MHT groups were small (16 and 40 women), and the largest 2026 cohort hasn't yet appeared in a journal.
• No study has tested any GH-releasing peptide in women on HRT. The estrogen-route effect is inferred from growth hormone studies, and tesamorelin's trials enrolled mostly men.
• PT-141, kisspeptin and topical GHK-Cu have no combination studies. The kisspeptin data come from an 8-woman infusion study.
• The teriparatide data come from two small randomized trials.

The bottom line

The only clinical outcome data on peptides plus HRT are for GLP-1 drugs and teriparatide. For GLP-1s the data are observational. For teriparatide they come from small randomized trials. For GH-releasing peptides, your estrogen route is a known variable that hasn't been tested with the peptides themselves. For everything else, "no known interaction" means it hasn't been studied, not that it's safe. Any decision on combining belongs with a physician who knows your full regimen.

Related on this site

• Peptides for Women: The 2026 Guide
• Peptides in Perimenopause and Menopause
• GLP-1s and Contraception: Planning Pregnancy
• Sexual Health Peptides for Women
• Age-Related GH Decline: Intervention Guide
• Labs Before and During Peptides
• Muscle Loss on GLP-1s: How to Prevent It

References

• Hurtado MD et al. Weight loss response to semaglutide in postmenopausal women with and without hormone therapy use. Menopause 2024 — retrospective cohort, n=106 (16 on HT). PMID 38446869
• Castaneda Hernandez R, Hurtado Andrade MD. Tirzepatide and menopausal hormone therapy. ENDO 2025 abstract — retrospective, n=120; conference data. Healio report
• Castaneda R et al. Menopause hormone therapy and weight loss response to GLP-1-based therapies in midlife women. The Menopause Society Annual Meeting 2026 — retrospective, >3,800 women; not yet peer-reviewed. Patient Care report
• Sánchez-Prieto M et al. Incretin-based therapies in peri- and postmenopausal women with obesity: Spanish Menopause Society position statement. Maturitas 2026 — calls the MHT link hypothesis-generating. PMID 42664617
• Tchang BG et al. Body weight reduction in women treated with tirzepatide by reproductive stage. Obesity 2025 — SURMOUNT post hoc analysis. PMID 40074721
• Kapitza C et al. Semaglutide does not reduce the bioavailability of the combined oral contraceptive. J Clin Pharmacol 2015 — interaction study in postmenopausal women. PMID 25475122
• Eli Lilly. Zepbound (tirzepatide) prescribing information, section 7.2. — oral contraceptive interaction. Label text
• Eli Lilly Medical. Can Zepbound be used with oral contraceptives or hormone replacement therapy? — oral HRT not studied. Lilly Medical
• FSRH Clinical Effectiveness Unit. Guidance on oral contraceptive use with GLP-1 agonists. — UK interim position. PDF
• Weissberger AJ et al. Contrasting effects of oral and transdermal routes of estrogen replacement therapy on 24-hour GH secretion, IGF-I and GH-binding protein. J Clin Endocrinol Metab 1991 — oral lowers IGF-1. PMID 1991807
• Davis SR et al. Effects of the route of estrogen administration on IGF-I, IGFBP-3 and insulin resistance. Menopause 2008 — 1-year RCT, route not dose. PMID 18806686
• Cook DM et al. Route of estrogen administration helps to determine GH replacement dose in GH-deficient adults. J Clin Endocrinol Metab 1999 — about double the GH dose on oral estrogen. PMID 10566634
• Khorram O et al. Endocrine and metabolic effects of long-term administration of a GHRH analogue in age-advanced men and women. J Clin Endocrinol Metab 1997 — small RCT; sex differences. PMID 9141536
• FDA. Egrifta WR (tesamorelin) prescribing information. 2025 — indication, CYP450/sex steroid note, IGF-1 monitoring. Label PDF
• EMA. Egrifta: withdrawal of the marketing authorisation application. 2012. EMA page
• Kingsberg SA et al. Bremelanotide for the treatment of HSDD: two randomized phase 3 trials. Obstet Gynecol 2019 — premenopausal women. PMID 31599840
• Vyleesi (bremelanotide) prescribing information. — not indicated after menopause; blood pressure and gastric emptying warnings. Label
• Lippincott MF et al. Continuous kisspeptin administration in postmenopausal women: impact of estradiol on LH secretion. J Clin Endocrinol Metab 2017 — n=8. PMID 28368443
• Thurston L et al. Effects of kisspeptin administration in women with HSDD. JAMA Netw Open 2022 — crossover fMRI RCT, premenopausal. PMID 36287566
• Davis SR et al. Global Consensus Position Statement on the Use of Testosterone Therapy for Women. J Clin Endocrinol Metab 2019. PMID 31498871
• Pickart L, Margolina A. Regenerative and protective actions of the GHK-Cu peptide in the light of the new gene data. Int J Mol Sci 2018 — review. PMID 29986520
• Lindsay R et al. Randomised controlled study of effect of parathyroid hormone on vertebral-bone mass and fracture incidence among postmenopausal women on oestrogen. Lancet 1997. PMID 9284777
• Cosman F et al. Parathyroid hormone added to established hormone therapy. J Bone Miner Res 2001 — RCT, n=52. PMID 11341338
• NAMS Advisory Panel. The 2022 hormone therapy position statement of The North American Menopause Society. Menopause 2022. PMID 35797481
• Goodwin Procter. FDA signals potentially evolving stance toward compounding of certain peptides. 2026 — April 2026 Category 2 removals and PCAC timeline. Goodwin