Peptide profile · Growth Hormone
Tesamorelin
The only FDA-approved peptide specifically designed to melt away stubborn belly fat by telling your brain to release more growth hormone naturally—working with your body's own systems rather than replacing them.
Written & reviewed by Michael Carroll · Research, Peptide Initiative
Typical dose
2 mg (1.4 mg with Egrifta SV/WR F8 formulation)
Half-life
26-38 minutes
Bioavailability
~100% (subcutaneous injection)
Molecular weight
5135.86 g/mol
Evidence level
Strong human trials
01 · Compound profile
Scientific & efficacy data
Molecular formula
C221H366N72O67S
Primary benefits
FDA-approved with Phase 3 trial data showing 15-18% reduction in dangerous belly fat—among the strongest evidence for any fat-targeting peptide
Significantly improves triglycerides, cholesterol ratios, and liver fat markers as visceral fat decreases
Increases IGF-1 levels by 100%+ while maintaining physiological feedback—works with your body's own systems
Theratechnologies Inc.
Amino acid sequence
Trans-3-hexenoic acid-Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Met-Ser-Arg-Gln-Gln-Gly-Glu-Ser-Asn-Gln-Glu-Arg-Gly-Ala-Arg-Ala-Arg-Leu-NH202 · Dosing
How much do I take?
2 mg (1.4 mg with Egrifta SV/WR F8 formulation) · once daily
Subcutaneous: A small injection into the fatty layer just under the skin — the same way insulin is given.
Bioavailability High — most of the dose reaches your bloodstream, just more gradually than an IV.
Best time to take
Inject in the morning on an empty stomach, at least 30 minutes before eating. This aligns with your natural cortisol awakening response and may optimize growth hormone release patterns.
With food?
Do NOT inject with food. Tesamorelin should be given on an empty stomach for optimal absorption. Wait at least 30 minutes after injection before eating breakfast.
If stacking
If using with other growth hormone secretagogues, separate injections by several hours. Some practitioners alternate between tesamorelin and other GHRH peptides rather than using them the same day. Never combine with exogenous GH—choose one or the other.
＋ Increase if
- +You've been on the starting dose for 4+ weeks with no issues
- +IGF-1 levels haven't increased meaningfully on lower doses
- +Your physician recommends the standard FDA-approved dose
－ Decrease if
- −You experience significant joint pain or swelling
- −Blood glucose levels rise substantially
- −Fluid retention becomes uncomfortable
- −Injection site reactions are severe or persistent
✓ Signs of right dose
- ✓Measurable reduction in waist circumference over 3-6 months
- ✓Improved triglyceride levels on blood work
- ✓IGF-1 levels in the upper normal range
- ✓Better body image and reduced belly appearance distress
Dosing Calculator
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03 · Suitability
Is this right for me?
Best for reducing visceral abdominal fat & improving metabolic health markers
Best for
People with Stubborn Visceral Fat
If you carry your weight around your midsection—the deep belly fat that wraps around your organs—tesamorelin is specifically designed for you. Unlike weight loss drugs, it targets visceral fat while preserving the normal subcutaneous fat that's healthy to have.
HIV Patients with Lipodystrophy
Tesamorelin is FDA-approved specifically for HIV-associated lipodystrophy—the abnormal fat accumulation in the belly that antiretroviral medications can cause. It's the only treatment proven to help this condition, reducing both the physical and psychological burden.
Those Concerned About Metabolic Health
Visceral fat isn't just cosmetic—it's metabolically dangerous, linked to heart disease, diabetes, and inflammation. By reducing visceral fat, tesamorelin also improves triglycerides, cholesterol ratios, and may help protect your liver from fatty liver disease.
Adults Wanting Natural GH Stimulation
Unlike synthetic growth hormone injections, tesamorelin works WITH your body's natural systems. It tells your pituitary to release more of YOUR OWN growth hormone, maintaining normal feedback loops and reducing the risks associated with supraphysiological GH levels.
Consider alternatives if
Do not use if
Use with caution if
Not sure?
Compare Tesamorelin with similar peptides to find the best fit for your goals.
04 · Administration
How do I use it?
Subcutaneous injection
Reconstitution — what you need
Example
For Egrifta SV (2mg vial): Add the entire contents of the provided sterile water diluent (0.5 mL) to the vial. This gives you a concentration of 4 mg/mL. The prescribed dose of 1.4 mg = 0.35 mL to inject.
At 4 mg/mL concentration: 1.4 mg dose = 0.35 mL (35 units on an insulin syringe). Always follow the specific reconstitution instructions for your particular product, as formulations differ.
Route
Subcutaneous injection (just under the skin into fatty tissue)—this is the only approved administration route
Best sites
Technique
- 01Wash hands thoroughly with soap and water
- 02Clean the injection site with an alcohol swab and let dry completely
- 03Pinch a fold of skin between thumb and forefinger
- 04Insert needle at a 45 to 90-degree angle (90 for more tissue, 45 for lean individuals)
- 05Inject slowly and steadily over 5-10 seconds
- 06Wait 5 seconds before withdrawing the needle
- 07Do not rub the injection site afterward
Storage · before reconstitution
Store powder in refrigerator at 36-46°F (2-8°C). Keep in original carton to protect from light. Do not freeze. Check expiration date on package—stable until that date if properly stored.
Storage · after reconstitution
Refrigerate reconstituted solution at 36-46°F (2-8°C). Use within 14 days for Egrifta SV (original Egrifta had shorter stability). Never freeze reconstituted solution. If solution becomes cloudy or contains particles, do not use.
Signs of degradation
Sample daily schedule
05 · Safety
Is it safe?
4 common side effects · 3 serious
Tesamorelin has a strong safety profile backed by FDA approval and multiple large Phase 3 clinical trials involving over 800 patients. The most common issues are injection site reactions and the typical side effects of elevated growth hormone (joint pain, fluid retention). Glucose metabolism should be monitored as some patients experience increased blood sugar. Long-term cardiovascular safety data is still being collected, which is why the FDA recommends reassessing treatment if visceral fat doesn't reduce.
Safety data comes from well-designed, placebo-controlled Phase 3 trials published in peer-reviewed journals and reviewed by the FDA. Studies extended up to 52 weeks with safety monitoring. This represents some of the strongest evidence available for any peptide therapy.
Common side effects · experienced by some users
Less common
These typically resolve with continued use or dose adjustment.
Stop and seek help if
- ×Severe allergic reaction occurs—stop immediately and seek emergency care
- ×Visceral fat has not decreased after 3 months of treatment (per FDA guidance)
- ×Blood glucose becomes uncontrolled despite adjustments
- ×Development of new or worsening malignancy
- ×Pregnancy occurs or is planned
- ×Intolerable side effects that don't resolve with dose adjustment
Tesamorelin is an FDA-approved prescription medication that should only be used under physician supervision. Never start, stop, or adjust your dose without consulting your prescribing healthcare provider. This information is educational and does not constitute medical advice.
With other peptides
- ✓CJC-1295 — Similar mechanism (GHRH pathway). Can be used together but may be redundant. Some practitioners alternate rather than combine.
- ✓Ipamorelin — Works on different receptor (GHRP). Can complement tesamorelin for enhanced GH release. Use at different times of day.
- ✓Sermorelin — Very similar mechanism (also GHRH analog). Generally not used together—choose one or the other.
- ✓BPC-157 — Different mechanism entirely (healing peptide). Safe to use together if addressing different goals.
With medications
- !Insulin — Tesamorelin can increase blood glucose, potentially requiring insulin dose adjustments. Monitor closely.
- !Oral diabetes medications — May need dose adjustment as tesamorelin affects glucose metabolism. Work with your endocrinologist.
- ✓Glucocorticoids (prednisone, etc.) — Steroids may reduce tesamorelin's effectiveness and counteract fat reduction benefits.
- !Growth hormone — Do not combine. Using both would be redundant and could cause excessive GH effects.
With supplements
- ✓Arginine — May have additive GH-releasing effects. Generally safe but probably unnecessary with tesamorelin.
- ✓Glucose disposal agents (berberine, etc.) — May help counteract tesamorelin's glucose-raising effects. Discuss with your doctor.
- ✓Fish oil — Safe to combine. May complement the triglyceride-lowering effects of tesamorelin.
- ✓Chromium — Safe. May help with blood sugar regulation.
06 · Effectiveness
How do I know it's working?
Strong human trials · first signs weeks 1-2
Evidence level
Strong human trials
(Phase 3 or FDA approved)
How it works
Your pituitary gland (a pea-sized gland at the base of your brain) releases growth hormone throughout the day, especially while you sleep. As we age, this release decreases. Tesamorelin is basically a messenger molecule that tells your pituitary to release more growth hormone naturally. It's almost identical to the 44-amino-acid signal your hypothalamus already makes, but with a small chemical modification that makes it last longer in your body. When growth hormone goes up, it signals your body to break down fat for energy—especially the dangerous visceral fat wrapped around your organs. The beauty is that you're not injecting growth hormone itself; you're just amplifying your body's own system.
Tesamorelin is a synthetic 44-amino-acid analog of human growth hormone-releasing hormone (GHRH) with a trans-3-hexenoic acid modification at the N-terminal tyrosine residue. This modification protects the molecule from rapid degradation by dipeptidyl peptidase-4 (DPP-4), extending its half-life while preserving full receptor binding activity. Upon subcutaneous injection, tesamorelin binds to GHRH receptors on somatotroph cells in the anterior pituitary, activating adenylyl cyclase via Gs-coupled signaling. This increases intracellular cAMP, which promotes growth hormone gene transcription and pulsatile GH secretion. The elevated GH stimulates hepatic IGF-1 production and directly promotes lipolysis in adipose tissue, with preferential effects on visceral adipose tissue. The mechanism for visceral fat selectivity may relate to differential expression of GH receptors and lipolytic enzymes between visceral and subcutaneous fat depots. Unlike exogenous GH administration, tesamorelin maintains physiological feedback regulation through somatostatin, reducing the risk of sustained supraphysiological GH levels.
What to expect
Weeks 1-2
What you might notice
- •Injection site reactions as your body adjusts
- •Possibly some joint stiffness or mild aching
- •May feel some fluid retention in hands or feet
- •No visible body composition changes yet
What's normal
- •Mild injection site redness or itching that resolves in 1-2 days
- •Slight puffiness in extremities, especially in the morning
- •Initial adjustment period discomfort
What's next
- →Continue with daily injections at consistent times
- →Track any side effects to discuss with your doctor
- →Side effects typically improve as your body adjusts
Weeks 3-8
What you might notice
- •Injection site reactions typically decrease significantly
- •IGF-1 levels rising on bloodwork (if tested)
- •May notice clothes fitting slightly differently around waist
- •Energy levels may improve as GH levels optimize
What's normal
- •Settling into the routine with manageable side effects
- •Subtle changes in how your midsection looks or feels
- •Better tolerance than the first couple weeks
What's next
- →Continue consistent daily dosing
- →Most practitioners recommend imaging (CT or MRI) at baseline and 12-26 weeks
- →Monitor blood glucose at regular intervals
Weeks 12-26
What you might notice
- •Measurable reduction in visceral fat (15-18% average in clinical trials)
- •Waist circumference decreasing noticeably
- •Improved triglyceride levels on bloodwork
- •Better body image and reduced belly-related distress
What's normal
- •Significant visceral fat reduction visible on imaging
- •Improved metabolic markers like triglycerides
- •Stable weight overall (tesamorelin is weight-neutral)
What's next
- →Discuss continuation with your physician
- →Benefits are maintained with continued treatment
- →Stopping treatment will cause visceral fat to return
Weeks 26-52 and beyond
What you might notice
- •Continued maintenance of reduced visceral fat
- •Sustained metabolic improvements
- •Possible continued incremental benefits
- •Long-term tolerance typically well-established
What's normal
- •Stable visceral fat reduction maintained at ~17-18% below baseline
- •Steady IGF-1 levels within normal range
- •Manageable or resolved side effects
What's next
- →Many patients continue indefinitely for maintenance
- →Regular monitoring of IGF-1 and glucose recommended
- →Reassess periodically with your healthcare provider
Signs it's working · Body Composition
- ✓Measurable decrease in waist circumference over 3-6 months
- ✓Reduction in visceral fat on CT or MRI imaging
- ✓Clothes fitting looser around the midsection
- ✓Reduced belly appearance distress or improved body image
Signs it's working · Metabolic Markers
- ✓Decreased triglyceride levels on blood tests
- ✓Improved cholesterol ratios (total cholesterol to HDL)
- ✓IGF-1 levels elevated into upper normal range
- ✓Stable or improved liver function tests
Signs it's working · Subjective Well-Being
- ✓Feeling less distressed about belly appearance
- ✓Improved self-image regarding body shape
- ✓Better energy levels throughout the day
- ✓Sense of metabolic health improvement
Not seeing results? Common reasons
- •Not injecting on an empty stomach—food can interfere with absorption and effectiveness
- •Inconsistent daily dosing—tesamorelin works best with consistent daily administration
- •Insufficient treatment duration—real visceral fat reduction takes 12-26 weeks to manifest
- •Unrealistic expectations—tesamorelin reduces visceral fat, not overall weight
- •Poor injection technique—ensure proper subcutaneous delivery, not intramuscular
- •Confounding medications like high-dose steroids that counteract the effects
Key research
07 · Questions
Frequently asked
Will tesamorelin help me lose weight?+
Tesamorelin is 'weight neutral'—you probably won't see the number on the scale change much. What changes is your body composition: visceral fat goes down significantly while other tissues stay stable. You might drop a pants size without losing pounds because visceral fat is being replaced by nothing (not muscle). If overall weight loss is your goal, consider GLP-1 medications like semaglutide instead.
How is tesamorelin different from growth hormone injections?+
Big difference! Growth hormone injections give you external GH that can suppress your own production and cause supraphysiological levels. Tesamorelin tells your pituitary to release more of YOUR OWN growth hormone, maintaining natural feedback loops and pulsatile release patterns. It's like turning up the volume on your natural system rather than replacing it with a synthetic one.
Why is it only FDA-approved for HIV patients?+
HIV-associated lipodystrophy (abnormal fat distribution from antiretroviral drugs) was the specific condition Theratechnologies targeted for approval because there was no treatment for it. The FDA approval process is disease-specific. However, the mechanism works in anyone with excess visceral fat—that's why physicians prescribe it off-label for non-HIV patients with similar issues.
What happens when I stop taking tesamorelin?+
Unfortunately, the visceral fat comes back. Clinical trials showed that patients who switched from tesamorelin to placebo regained their visceral fat within 26 weeks. This means tesamorelin is typically a long-term or indefinite treatment if you want to maintain the benefits. Think of it like blood pressure medication—it works while you take it.
Will tesamorelin affect my blood sugar?+
It can, which is why monitoring is important. Growth hormone has anti-insulin effects, so fasting glucose and HbA1c can increase in some patients. Clinical trials showed that most patients had only mild changes that didn't reach clinical significance, but if you have pre-diabetes or diabetes, you need closer monitoring and possible medication adjustments.
Can I use tesamorelin for bodybuilding?+
While tesamorelin does increase GH and IGF-1, it's not ideal for bodybuilding purposes. It's specifically designed to reduce visceral fat, not build muscle. The GH increase is more modest than what bodybuilders typically seek with other secretagogues or direct GH. If muscle growth is your primary goal, other peptide combinations might be more appropriate.
How long until I see results?+
Most visible and measurable changes occur between weeks 12-26. You might notice subtle changes earlier (clothes fitting differently, less bloating), but the significant 15-18% reduction in visceral fat that clinical trials demonstrated takes several months of consistent daily use. Patience and consistency are key.
Is tesamorelin safe to use long-term?+
Clinical trials studied tesamorelin for up to 52 weeks and found it well-tolerated with manageable side effects. Many patients use it indefinitely since stopping causes visceral fat to return. However, long-term cardiovascular safety data is still being collected, which is why the FDA recommends reassessing if you don't see visceral fat reduction. Regular monitoring of IGF-1 and glucose is recommended for extended use.
08 · Further reading
History & related research
History · since 1995
The Canadian Peptide That Gave HIV Patients Their Bodies Back
When AIDS drugs saved lives but stole patients' appearances, a small Montreal company created a solution. Tesamorelin became the first and only treatment for a condition no one talked about — the fat redistribution that made HIV survivors look sick even when they weren't.
Read the full history of Tesamorelin