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Hormones & growth

Tesamorelin

A stabilised GHRH analogue that prompts the body's own growth-hormone release. Known for selectively reducing visceral belly fat.

5 min read 13 sources

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Approved · in the USA since 2010Lab tested in the shop

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Summary

At a glance

Sources checked on 25 Oct 2026

Target
1 receptor

GHRH receptor of the pituitary, as an agonist according to ChEMBL13

Half-life
8 minutes

after a single dose per the US prescribing information, given once a day in trials11

Visceral belly fat
-15.2 %

Phase 3 at 26 weeks (placebo +5.0%)1

Normal liver fat
35 %

Share below 5% liver fat after 12 months (placebo 4%)6

Phase 3 in the registry
2 trials

both completed, as of 25 Oct 202612

  • Tesamorelin is a stabilised GHRH analogue: the 44 amino acids of human GHRH plus a small protecting group. It binds to the GHRH receptor of the pituitary.1113
  • In two phase 3 trials visceral belly fat fell by 15.2 and 10.9 percent in 26 weeks. On placebo it rose by 5.0 percent or fell by 0.6 percent, while subcutaneous fat stayed largely the same.13
  • In two studies in people with HIV liver fat went down as well. After twelve months 35 percent had normal liver fat, 4 percent on placebo.56
  • The most common effects were injection-site reactions and joint pain. IGF-1 rose clearly and in a small share long-term blood sugar (HbA1c) rose into the diabetes range.111
  • In the US Tesamorelin has been approved since 2010 for a narrow use: excess belly fat in HIV with lipodystrophy. Everything here is the state of research, not a recommendation.1113
Profile

Updated May 2026

How long does it stay in the body?

Share left after one dose, calculated with a half-life of ~32 minutes

Half-life ~32 minutes
After 64 minutes: 25 %
Minute 32 · 50 %Minute 64 · 25 %Minute 96 · 12.5 %Minute 160 · 3.1 %

Simplified model without an absorption phase, half-life from the TPD lexicon. The lexicon gives 26 to 38 minutes, we calculate with the middle.

Class
GHRH analogue

GH secretagogue

Frequency
Daily

subcutaneous, usually evening

Half-life
26 to 38 minutes

after 14 days of dosing

Form
Lyophilised powder

reconstituted with BAC water

Sizes
2 to 20 mg

4 sizes in the shop

Contents 16 sections
  1. At a glance
  2. What is Tesamorelin?
  3. How it works
  4. What you need
  5. Reconstitution
  6. Injection
  7. Dosing
  8. What the research shows
  9. Research status
  10. Side effects
  11. Lifestyle
  12. Storage
  13. Related compounds
  14. FAQ
  15. Glossary
  16. Sources

What is Tesamorelin?

Tesamorelin is a stabilised GHRH analogue, a synthetic version of growth-hormone-releasing hormone. It is not growth hormone (GH) itself, but nudges the pituitary to release the body's own GH in natural pulses. That is the key difference from direct GH: the body keeps control over the amount and rhythm.

Unlike the GLP-1 compounds, Tesamorelin is injected daily, usually in the evening. The half-life is very short, per the US prescribing information 26 minutes in healthy subjects and 38 minutes in HIV patients after 14 days of dosing (for newer formulations only 8 to 11 minutes after a single dose). The GH pulse it triggers and the later rise in IGF-1 act for far longer, though. It ships as a freeze-dried powder you dissolve in bacteriostatic water before the first use.

Comparison

GHRH, ghrelin or the hormone itself

Where each compound acts, as stated in the TPD lexicon. Tap a card to open its entry.

GHRH analogue, short Sermorelin GHRH GHRH analogue, long CJC-1295 with DAC GHRH Ghrelin mimetic Ipamorelin Ghrelin Growth hormone itself HGH 191AA (Somatropin) GH
GHRH analogue, stabilised Tesamorelin GHRH

How it works

Tesamorelin binds the GHRH receptors on the pituitary and triggers a GH pulse there, similar to the one that naturally happens in deep sleep. The released GH drives IGF-1 production in the liver. A large part of the effects run through that.

In research, Tesamorelin is mainly known for one thing: it selectively reduces visceral belly fat, the fat deep in the abdomen around the organs. It does so fairly specifically, without strongly touching the subcutaneous fat. Alongside that, a positive effect on liver fat and, in one study, on cognitive performance in older subjects has been observed.

Where it acts

One receptor, several organs

Tap a point or a card. Colour = receptor, grey = effect seen in trials.

  1. Pituitary

    Releases the body's own growth hormone in pulses11

    GHRH
  2. Liver

    Liver fat fell in two studies in HIV6

    Observed in trials
  3. Belly fat

    Visceral fat fell, subcutaneous fat stayed nearly the same1

    Observed in trials
  4. Blood lipids and vessels

    Triglycerides fell, carotid artery wall slightly thinner7

    Observed in trials
  5. Blood sugar

    HbA1c of 6.5% or more in 5 versus 1 percent on placebo11

    Observed in trials

Targets in the ChEMBL database13

Compound CHEMBL1237026: one recorded mechanism, agonist with direct binding to the human receptor.

GHRH receptor
Gene
GHRHR
UniProt
Q02643
ChEMBL
CHEMBL2032
Action
Agonist, direct binding
Glass gland model sending light waves to a cluster of pale fat cells, surrounded by blue 3D peptide chains
Symbolic image.

What you need

Before you start, have everything ready. Because Tesamorelin is injected daily, you need more needles accordingly:

Supplies

5 things, numbered as in the picture

Tick off what you already have. Vial and BAC water are our real shop photos at the same size.

Tesamorelin vial and bacteriostatic water at the same size with the black TPD label, next to two U-100 insulin syringes, two alcohol swabs and a sharps container with a blue lid

  1. Tesamorelin vial

    The Tesamorelin vial with the freeze-dried powder

    In the shop

  2. Bacteriostatic water

    Bacteriostatic water to dissolve it

    In the shop

  3. U-100 insulin syringes

    U-100 insulin syringes for the daily injections

    Amazon (opens a new tab)

  4. Alcohol swabs

    Alcohol swabs for the vial cap and the skin

    Amazon (opens a new tab)

  5. Sharps container

    A sealable sharps container for used needles

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With everything clean and in one place, the rest is straightforward.

Reconstitution

The powder is dissolved in bacteriostatic water. How much water you add sets the concentration and therefore how many units you draw on the insulin syringe for your dose.

Use the peptide calculator for exactly this: pick your vial size and the water volume to instantly see the concentration and the units per dose. Roughly: less water means higher concentration and fewer units.

When dissolving, just add the bac water, it does not matter if it hits the powder directly. Then swirl or shake until everything has dissolved, both are fine.

Step by step

Dissolving the powder

Four steps, the same for every vial size.

  1. 1Wipe the cap

    Clean the rubber stopper with an alcohol swab.

  2. 2Add BAC water

    Just add it, it does not matter if it hits the powder directly.

  3. 3Swirl or shake

    Until everything has dissolved, both are fine.

  4. 4Draw up

    With the U-100 insulin syringe.

Less water higher concentration fewer units on the syringe Example: 10 mg + 2 ml = 5 mg/ml

Injection

The injection is subcutaneous, into the fat layer under the skin, classically into the abdomen (keep about two finger-widths clear of the navel). Many inject in the evening, because the natural GH pulse comes during deep sleep anyway and the effect leans on that.

The short version:

  • Clean the spot with an alcohol swab and let it dry
  • Pinch up a small fold of skin
  • Insert the needle: at 90 degrees where there is more fat under the skin, at 45 degrees in lean people with little fat
  • Inject slowly, wait a moment, then withdraw
  • Put the needle straight into the sharps container

Rotate the site day to day. Exactly because this is injected daily, that matters so the tissue does not get irritated.

Dosing

Dosing

Dosing, titration and syringe

Loading the dosing information …

  • Getting started and stepping up, drawn as a staircase
  • Units on the U-100 syringe for every step
  • How long one vial lasts

What the research shows

Tesamorelin is well studied. In the registration-grade trial (Falutz, 2007), 2mg per day over six months selectively reduced visceral belly fat while subcutaneous fat stayed largely untouched. A later trial (Stanley, 2014) confirmed this and additionally showed a drop in liver fat. In a cognition study (Baker, 2012), tesamorelin over 20 weeks had a positive effect on executive function in older subjects, while memory showed only a trend.

The individual studies with links are in the source block below.

Study results

What the trials measured

Interactive: switch tabs, tap points, show or hide arms. Arms are named relative to each other, no dosing advice.

Visceral belly fat at 26 weeks134

Mean change in percent, measured by CT in people with HIV and excess belly fat

Phase 3 trial 11 412 participants, 26 weeks
Placebo +5.0%
Tesamorelin -15.2%
Phase 3 trial 23 404 participants, 26 weeks
Placebo -0.6%
Tesamorelin -10.9%
52 weeks continuously4 Both trials pooled, only those on Tesamorelin for a full year
Tesamorelin -17.5%

Values as stated in the trial abstracts. Subcutaneous belly fat barely changed. Those who switched to placebo after 26 weeks quickly lost the effect again.

Liver fat at 6 months5

Median change in liver fat content (lipid to water) in percentage points, 50 participants with HIV

Study on belly and liver fat5 Measured by MR spectroscopy
Placebo +0.9 pp
Tesamorelin -2.0 pp

The net difference was 2.9 percentage points in favour of Tesamorelin. The study was small and designed as a preliminary trial.

Liver fat below 5% after 12 months6

Share of participants with normal liver fat, 61 people with HIV and fatty liver

Fatty liver study6 Twelve months, double-blind against placebo
Placebo 4%
Tesamorelin 35%

Compared with placebo liver fat fell by 4.1 percentage points in absolute terms, 37 percent relative to baseline. Fasting glucose and HbA1c did not differ after twelve months.

IGF-1 at 26 weeks1

Mean change in blood level in percent, phase 3 trial 1

Phase 3 trial 11 412 participants with HIV
Placebo -5%
Tesamorelin +81%

IGF-1 is made mainly in the liver when growth hormone is released. Per the US prescribing information it was clearly above the age-adjusted range in 47 percent of treated patients after 26 weeks.

Glass liver model and a cluster of yellowish fat cells, surrounded by glowing trails of light
Symbolic image.

Research status

Where the research stands

From lab experiments to approval in the USA: registered trials with status, participants and results. As of 25 Oct 2026. 12

  1. Preclinical Binding to the GHRH receptor in the lab
  2. Phase 1 2 trials, 2 completed
  3. Phase 2 7 trials, 5 completed
  4. Phase 3 2 trials, 2 completed
  5. Approval in the USA since 2010
675 participants in phase 3 Approved in the US since 2010, only for excess belly fat in HIV with lipodystrophy. ChEMBL lists Tesamorelin with phase 4 as the highest phase.13
Show all 9 phase 2 and 3 trials on a timelineHide timeline 7 completed 2 running 5 with results
Phase 2
Phase 3

Bar: start to primary endpoint (planned for running trials). Green = completed, blue = progress until 25 Oct 2026. Phase 1: 2 trials on safety and pharmacokinetics, not shown as bars.

Side effects

The side effects are the ones you know from elevated GH: water retention, joint or muscle aches, occasionally tingling or numbness in the hands (carpal-tunnel-like). Per the US prescribing information, these complaints are usually transient or resolve after stopping. On top of that come injection-site reactions, which are among the most common side effects. The prescribing information also warns of glucose intolerance (an HbA1c of 6.5% or more occurred after 26 weeks in 5% on tesamorelin and 1% on placebo), so a look at blood sugar is worthwhile with longer use. After 26 weeks, IGF-1 was above the age-adjusted normal range in almost half of treated patients. 4% had hypersensitivity reactions such as itching, redness, flushing or rash.

Tolerability

Frequency in the phase 3 trials

Out of 100 participants per group, how many had the event in the first 26 weeks.

6 of 100 Placebo
17 of 100 Tesamorelin
Event PlaceboTesamorelin
Injection-site reaction11 6%17%
Joint pain11 11%13%
Muscle pain11 2%6%
Fluid retention in legs or arms11 2%6%
Tingling (paraesthesia)11 2%5%
HbA1c of 6.5% or more11 1%5%

Rounded values from the US prescribing information (543 participants on Tesamorelin, 263 on placebo). Per that document fluid retention, joint pain and carpal tunnel complaints are mostly transient or resolve after stopping.11

Lifestyle

Tesamorelin works through your own GH rhythm, so a few things get a lot more out of it:

  1. Sleep

    The natural GH pulse comes in deep sleep. Good, sufficient sleep and the evening dose work together.

  2. Spacing from meals

    Insulin blunts GH release, so the evening dose is often given with some gap from the last big meal.

  3. Resistance training

    GH and IGF-1 do their best when the training stimulus is there.

  4. Enough protein for recovery.

Pillow with a light blue sleep mask, a glass of water on the bedside table and two dumbbells on the rug in evening light

Anyone who sleeps badly anyway or eats large amounts right before bed gives away part of the effect.

Storage

The undissolved powder is robust, normal room temperature (around 20 to 25 degrees) is fine, ideally kept in the dark. Once dissolved, the solution goes into the fridge (2 to 8 degrees) and stays stable there for at least 4 to 6 months with barely any loss of potency, in practice considerably longer. The bacteriostatic water brings a preservative that keeps the dissolved form stable for longer.

Shelf life

How long it keeps

Undissolved (powder) Room temperature, around 20 to 25 degrees, dark

Robust, no fridge needed. Keeps for several months without trouble.

Dissolved (mixed) Fridge, 2 to 8 degrees

At least 4 to 6 months with barely any loss of potency. The bacteriostatic water brings a preservative.

  • Keep it dark
  • Dissolved: 2 to 8 degrees
  • Note the mixing date on the vial
Nine vials with white powder and blue caps in the door shelf of a bright fridge
Powder dark at room temperature, once dissolved into the fridge (2 to 8 degrees), stable there for at least 4 to 6 months. Symbolic image.
Level · Tesamorelin

How the level builds up

One dose per day: each dose adds to what is left of the previous one.

Lexicon: Daily (subcutaneous), usually evening
Peak 1×Trough 0×
Day 1 · 2. dose
1× of the first dose
Plateau
from Day 0

100 % of the plateau after dose 1

Peak
1×

of the first dose

Trough
0×

before the next dose

Simplified model, values relative to the first dose, no dosing information. Dashed: the first dose alone, green: the plateau.

Related

Related compounds

Same receptors, blends with Tesamorelin or a different path: all in the TPD lexicon.

Tesamorelin
Sermorelin GHRH analogue, only the first 29 amino acids CJC-1295 without DAC Short-acting GHRH analogue CJC-1295 with DAC Long-acting GHRH analogue Ipamorelin Different path: ghrelin receptor MK-677 (Ibutamoren) Ghrelin receptor, studied as a tablet HGH 191AA (Somatropin) Growth hormone directly instead of via the pituitary IGF-1 LR3 Acts at IGF-1, one step further down Tesa + Ipa Blend Contains Tesamorelin plus ipamorelin Reta + Tesamorelin Blend Contains Tesamorelin plus retatrutide

FAQ

Common questions about Tesamorelin

Short answers, each backed by the sources below.

Is Tesamorelin approved?

In the US yes, since 2010. The approval is narrow: excess belly fat in adults with HIV and lipodystrophy. Per the US prescribing information it is explicitly not indicated for weight loss. ChEMBL lists Tesamorelin with phase 4 as the highest phase.1113

How does Tesamorelin differ from growth hormone?

Tesamorelin is not growth hormone. It activates the GHRH receptor of the pituitary, which then releases its own growth hormone in pulses. In response mainly the liver makes more IGF-1. In the first phase 3 trial IGF-1 rose by 81 percent in 26 weeks, on placebo it fell by 5 percent.111

What did the phase 3 trials show?

Two trials with more than 800 people with HIV and excess belly fat in total. After 26 weeks visceral fat fell by 15.2 and 10.9 percent, on placebo it rose by 5.0 percent or fell by 0.6 percent. Those on Tesamorelin for a full year were at minus 17.5 percent. Triglycerides fell too, glucose values did not change in a clinically meaningful way on average.134

What happens after stopping?

The effect only lasts while Tesamorelin is given. In both phase 3 trials visceral fat quickly returned in those who switched to placebo after 26 weeks. With continued dosing the reduction stayed stable over 52 weeks.23

What about liver fat?

In a small study with 50 people with HIV liver fat content fell by a median of 2.0 percentage points in 6 months, on placebo it rose by 0.9. In a second study with fatty liver 35 percent had normal liver fat below 5 percent after twelve months, 4 percent on placebo.56

Is there data without HIV?

Few. In a study with 60 people with excess belly fat and low growth hormone release visceral fat fell by 16 square centimetres in twelve months, on placebo it rose by 19. In older adults one study over 20 weeks found a positive effect on executive function. A later study in HIV found no clear difference in cognition.789

Which side effects were seen?

Most often injection-site reactions (17 versus 6 percent) and joint pain. Typical effects of more growth hormone such as fluid retention and tingling in the hands came on top. An HbA1c of 6.5 percent or more occurred in 5 percent, 1 percent on placebo. 4 percent had hypersensitivity reactions such as itching or rash.11

How long does Tesamorelin stay in the body?

Only briefly. Per the current US prescribing information the half-life after a single dose is about 8 minutes. The trials gave it once a day. IGF-1 stayed raised throughout, by 81 percent on average after 26 weeks.111

Glossary

Terms explained briefly

Dotted words in the text open these explanations directly.

Carpal tunnel syndrome
Pressure on a nerve at the wrist, often from fluid retention. Typical signs are tingling and numbness in the fingers.
GHRH
Growth hormone-releasing hormone: a hormone from the hypothalamus that prompts the pituitary to release growth hormone. An analogue is a synthetically modified version of it.
Growth hormone (GH)
Pituitary hormone. It is released in pulses (mostly in deep sleep) and promotes fat breakdown and tissue build-up.
Half-life
Time after which only half of a substance is left in the blood. For Tesamorelin it is only minutes.
HbA1c
Long-term blood sugar: reflects average blood sugar over the past eight to twelve weeks. From 6.5 percent it counts as diabetes.
IGF-1
Insulin-like growth factor 1: messenger made mainly by the liver under growth hormone. Many effects of GH run through it.
Lipodystrophy
Disturbed fat distribution: fat builds up at the belly and is lost from arms and legs. It was common under older HIV therapies.
Lyophilisate
Freeze-dried powder. Without water a peptide keeps much longer.
Pituitary
Small gland below the brain (hypophysis). It controls many hormones, including growth hormone.
Placebo
Dummy preparation without active substance. Comparing against it shows what is due to the substance itself.
Receptor
Protein on the cell surface that a messenger docks onto. Only then does the cell respond.
Subcutaneous
Into the fat layer just under the skin.
Subcutaneous fat
Fat layer just under the skin. It stayed largely the same in the Tesamorelin trials.
Visceral fat
Fat deep in the abdomen around the organs, as opposed to subcutaneous fat. Trials measure it by CT.

Evidence

Sources

Show all 13 sourcesHide sources 10 Studies1 Trial registry2 Database checked 25 Oct 2026

Studies

  1. Phase 3 trial 1 on belly fat in HIV

    Falutz et al., New England Journal of Medicine, 2007

    DOI 10.1056/NEJMoa072375 PMID 18057338 NCT00123253
    Checked 25 Oct 2026 via doi.org, Crossref, PubMed
  2. Extension of trial 1 to 52 weeks

    Falutz et al., AIDS, 2008

    DOI 10.1097/QAD.0b013e32830a5058 PMID 18690162
    Checked 25 Oct 2026 via doi.org, Crossref, PubMed
  3. Phase 3 trial 2 with extension

    Falutz et al., Journal of Acquired Immune Deficiency Syndromes, 2010

    DOI 10.1097/QAI.0b013e3181cbdaff PMID 20101189 NCT00608023
    Checked 25 Oct 2026 via doi.org, Crossref, PubMed
  4. Pooled analysis of both phase 3 trials

    Falutz et al., Journal of Clinical Endocrinology & Metabolism, 2010

    DOI 10.1210/jc.2010-0490 PMID 20554713
    Checked 25 Oct 2026 via doi.org, Crossref, PubMed
  5. Study on visceral fat and liver fat

    Stanley et al., JAMA, 2014

    DOI 10.1001/jama.2014.8334 PMID 25038357 NCT01263717
    Checked 25 Oct 2026 via doi.org, Crossref, PubMed
  6. Study on fatty liver in HIV

    Stanley et al., The Lancet HIV, 2019

    DOI 10.1016/S2352-3018(19)30338-8 PMID 31611038 NCT02196831
    Checked 25 Oct 2026 via doi.org, Crossref, PubMed
  7. Study on belly fat in obesity without HIV

    Makimura et al., Journal of Clinical Endocrinology & Metabolism, 2012

    DOI 10.1210/jc.2012-2794 PMID 23015655 NCT00675506
    Checked 25 Oct 2026 via doi.org, Crossref, PubMed
  8. Study on cognitive performance in older adults

    Baker et al., Archives of Neurology, 2012

    DOI 10.1001/archneurol.2012.1970 PMID 22869065 NCT00257712
    Checked 25 Oct 2026 via doi.org, Crossref, PubMed
  9. Phase 2 study on cognition in HIV

    Ellis et al., Journal of Infectious Diseases, 2025

    DOI 10.1093/infdis/jiaf012 PMID 39813152 NCT02572323
    Checked 25 Oct 2026 via doi.org, Crossref, PubMed
  10. Pilot study on cognition and brain connectivity

    Stewart et al., eNeurologicalSci, 2026

    DOI 10.1016/j.ensci.2026.100616 PMID 42382101 NCT02553603
    Checked 25 Oct 2026 via doi.org, Crossref, PubMed

Trial registry

  1. All trials on ClinicalTrials.gov

    ClinicalTrials.gov, U.S. National Library of Medicine

    Checked 25 Oct 2026 via ClinicalTrials.gov API v2

Database

  1. US prescribing information (mechanism, trials, side effects)

    DailyMed, U.S. National Library of Medicine, Fassung Juli 2026

    Checked 25 Oct 2026 via DailyMed
  2. Mechanism and target in ChEMBL

    ChEMBL, EMBL-EBI (CHEMBL1237026)

    Checked 25 Oct 2026 via ChEMBL

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