Clinically reviewed by Dr. Ponlawat Pitsuwan, Physician, Takecare Clinic Phuket.
Last reviewed: October 2026
GLP-1 receptor agonists like semaglutide and tirzepatide can produce meaningful weight loss in women over 40, but perimenopause and menopause change how your body responds to them. Falling estrogen reduces insulin sensitivity and may dampen the appetite-suppression signal these medications rely on. Results are still achievable, but they often require adjusting the approach, protecting muscle mass, and in some cases combining treatment with hormone therapy.
You have been living in Chalong for two years, eating well, staying active, and you started a GLP-1 injection six months ago. The first three months went well. Then your cycle became irregular, the weight stopped shifting, and you are wondering whether the medication has stopped working or whether something else has changed. This pattern is well recognised in women over 40 managing menopause weight gain while on GLP-1 therapy.
The medication has not stopped working. What changed is the hormonal environment it is working in. Perimenopause and menopause shift your metabolism in ways that alter how your body responds to these drugs. Understanding that shift is the first step to getting your results back on track.

Why Menopause Changes Your Body’s Response to GLP-1
GLP-1, short for glucagon-like peptide-1, is a hormone your gut releases after eating. It signals to your brain that you are full and slows how quickly your stomach empties. Drugs like semaglutide and tirzepatide mimic and amplify that signal.
Estrogen helps maintain the sensitivity of the receptors these drugs bind to, particularly in the part of the brain that regulates appetite. As estrogen falls during perimenopause, those receptors become less responsive. The medication is still arriving at the right address, but the door is harder to open.
Falling estrogen also worsens insulin resistance, the state where your cells do not respond normally to insulin. This makes blood sugar harder to regulate and creates conditions where fat storage around the abdomen accelerates. GLP-1 medications address insulin resistance directly, but they are competing against a background that is actively working against them.
There is a cortisol piece too. Estrogen normally helps buffer your stress response. As it drops, cortisol becomes less regulated, and elevated cortisol promotes abdominal fat storage independent of what you eat. This is not a reason to stop treatment. It is a reason to understand why results may be slower than they were in your thirties.
How Fat Redistribution in Menopause Affects Treatment Goals
Before menopause, fat tends to sit in the hips and thighs, just under the skin. After menopause, more fat accumulates around the organs in the abdominal cavity. This is not just a cosmetic difference.
That visceral fat drives inflammation, worsens insulin resistance, and raises cardiovascular risk. The good news is that GLP-1 medications appear to reduce central adiposity, based on post hoc data from the SURMOUNT trials showing meaningful waist circumference reductions across pre-, peri-, and postmenopausal women. Whether the reduction is specifically preferential for visceral over subcutaneous fat in this group has not been confirmed from menopausal subgroup imaging data.
This means that even when the scale moves slowly, significant metabolic improvement may already be happening. Waist circumference is a more useful measure of progress in this group than weight alone.

The Muscle Loss Risk Every Woman Over 40 Needs to Know
This is the part most women are not told before they start. Weight loss on GLP-1 medications is not pure fat loss. Data presented at ENDO 2025 flagged that approximately 40 to 48 percent of weight lost on semaglutide may be lean mass in a small observational study of 40 adults. Older age and female sex were linked to greater lean mass loss. Whether postmenopausal women specifically are at the highest risk has not yet been established, and larger randomised trials are needed.
Why does this matter more after menopause? Estrogen normally helps preserve muscle tissue. When it drops, you lose one of the body’s natural defences against muscle breakdown. Add a significant calorie reduction from GLP-1 appetite suppression on top of that, and lean mass can fall faster than most patients expect.
The response is straightforward. Protein intake should be adequate, with current nutrition guidance for midlife women pointing to a higher daily target than the general adult recommendation. Resistance training two to three times per week has solid evidence for preserving lean mass during weight loss. These are not optional extras for women over 40 on GLP-1 therapy. They are part of the treatment.
Track body composition, not just weight. A DEXA scan or bioimpedance assessment gives you the lean mass versus fat mass split. If your weight is stable but your lean mass is dropping, that is worth discussing at your next review.
Can You Take GLP-1 with HRT
This is a question that comes up often in clinical practice. The evidence is more reassuring than most people expect.
Several observational studies published in 2025 and 2026 have looked at the combination of GLP-1 therapy with menopausal hormone therapy. The signal that emerges is that the two treatments may work better together than either does alone for some women, particularly those not seeing strong results from GLP-1 in isolation. These are observational findings and randomised trial data are not yet available.
Estrogen replacement may restore some of the receptor sensitivity that perimenopause reduced, making the GLP-1 medication more effective at suppressing appetite. Whether to pursue this combination is a clinical decision that depends on your personal medical history, particularly your cardiovascular history and any contraindications to hormone therapy. You can discuss whether GLP-1 can be taken with HRT at Takecare Clinic Phuket with an English-speaking physician.
Perimenopause vs Postmenopause: Does Timing Matter?
Clinically, perimenopause and postmenopause are quite different metabolic states, and treating them as one thing leads to poor decisions.
Post hoc data from the SURMOUNT trials for tirzepatide showed broadly comparable weight loss results across menopausal stages, with roughly 23 percent body weight reduction in both perimenopausal and postmenopausal women versus about 3 percent with placebo. That is reassuring. But observational data also suggests postmenopausal women who combine GLP-1 therapy with hormone therapy tend to sustain results better than those on GLP-1 alone.
If you are in perimenopause and your results have stalled, fluctuating estrogen may be the driver. If you are postmenopausal and results were never strong, the case for discussing hormone therapy alongside your GLP-1 is worth raising with your doctor.
Monitoring Markers That Matter Beyond the Scale
For menopausal women on GLP-1 therapy, weight is the least informative number you can track. Waist circumference and waist-to-hip ratio show you whether visceral fat is changing. Fasting glucose and HbA1c, a three-month average of blood sugar control, tell you about metabolic improvement. A fasting lipid panel and blood pressure round out the picture.
A blood test in Phuket covers the metabolic markers in a single visit. If you are an expat or long-stay resident without an ongoing GP relationship, a health check-up at Takecare Clinic Phuket sets a baseline before you start treatment and gives you something meaningful to compare at three and six months.
Stable weight with a narrowing waist, improving HbA1c, and preserved lean mass is a successful treatment outcome in this group. Do not let the scale be the only judge.
Starting GLP-1 Therapy in Phuket as an Expat or Long-Stay Visitor
For many women living or spending extended time in Phuket, accessing GLP-1 treatment involves practical challenges that have nothing to do with the medication itself. There is no home GP to write a referral. A prescription may have run out. And storage in a tropical climate raises real questions about keeping injectable medications viable.
These are solvable problems. Semaglutide and tirzepatide are available in Thailand. At Takecare Clinic Phuket, you can walk in without an appointment, be assessed by an English-speaking physician, have baseline blood work arranged, and start a prescription if you are a suitable candidate.
One practical note worth raising at your first visit: injectable GLP-1 medications require refrigeration. If you are moving between a villa in Bang Tao, a Kata guesthouse, and a liveaboard off Phi Phi, discuss storage logistics during your first consultation rather than after a medication error. Cold-chain management in Phuket’s heat is a specific problem, and it is one that catches people off guard.
Ready to start or review your GLP-1 treatment in Phuket?
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If you are a woman over 40 managing weight during perimenopause or menopause, GLP-1 therapy may be part of the answer, but starting safely and monitoring correctly matters. At Takecare Clinic Phuket, an English-speaking physician can assess whether GLP-1 treatment is appropriate for you, arrange baseline blood tests, discuss whether hormone therapy is relevant to your situation, and set up a monitoring plan you can follow whether you are based on the island long-term or visiting for an extended stay. Walk in without an appointment, across all of Phuket including Patong, Kata, Karon, Chalong, Rawai, Bang Tao, and Phuket Town.
FAQ
Dr. Ponlawat Pitsuwan
Physician, Takecare Medical Clinic Phuket
a walk-in medical clinic based in Patong with no appointment needed and English-speaking physician care for the whole island. He sees tourists, expats, and long-stay residents across Phuket for weight management consultations, GLP-1 therapy assessments, metabolic health monitoring, and ongoing chronic disease management including care for women navigating perimenopause and menopause. His focus is straightforward, evidence-based care delivered in plain language.
References
- Wilding JPH et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. New England Journal of Medicine, 2021.
- Jastreboff AM et al. Tirzepatide Once Weekly for the Treatment of Obesity (SURMOUNT-1). New England Journal of Medicine, 2022.
- Endocrine Society. ENDO 2025 Press Release: Consuming More Protein May Protect Patients Taking Anti-Obesity Drug from Muscle Loss. Endocrine Society, 2025.
- American College of Cardiology. ATTAIN-1: Oral Orforglipron Significantly Reduces Weight, Cardiometabolic Risk. ACC Journal Scan, 2025.
- Healio. Hormone therapy plus GLP-1 may equal greater, sustainable weight loss for menopausal women. Healio, October 2026.
- MIMS. Tirzepatide reduces weight in women with obesity across reproductive stages (SURMOUNT post hoc analysis). MIMS, 2025.
The information in this article is for educational purposes only and does not constitute medical advice. It should not be used to self-diagnose or replace a consultation with a qualified physician. If you have concerns about your health, contact a licensed medical professional. For appointments at Takecare Clinic Phuket, visit takecareclinicphuket.com.

