Tesamorelin (Egrifta): research, side effects and approved dosage
In short
Tesamorelin is a peptide similar to growth hormone-releasing hormone that is an approved medicine in the United States for excess abdominal fat in people with HIV [5]regulator. It has no marketing authorisation in the EU [4]regulator.
- Tesamorelin increases the body's own growth hormone release. It is not growth hormone itself [1]A [4]regulator.
- The best evidence comes from randomised placebo-controlled trials in people with HIV: visceral fat fell by about 15% with tesamorelin, while with placebo it stayed the same or rose [1, 2]A.
- Weakness: the fat came back when treatment stopped [12]A, and according to the EU medicines committee no health benefit was shown [4]regulator.
- According to the label, tesamorelin is not indicated for weight loss [10]official. Outside HIV the studies are small [14]B, and there are no treatment studies in athletes.
- In Finland tesamorelin is in Annex 1 of the medicines list, so it is controlled as a medicine [7]regulator. In sport it is prohibited (WADA S2.2.4) [8]regulator.
What is tesamorelin?
Tesamorelin is a peptide that resembles the body's own growth hormone-releasing hormone (GRF or GHRH). In the body this hormone makes the pituitary gland release growth hormone, and growth hormone plays a role in how fat tissue is formed and broken down [4]regulator.
In the United States the FDA approved tesamorelin under the name Egrifta in November 2010 [5]regulator. The current products are Egrifta WR and Egrifta SV [10, 11]official. In the EU the application for marketing authorisation was withdrawn in 2012 [4]regulator.
Basics: What are peptides?. All substances: Peptides A-Z.
For comparison: approved or not: IGF-1 LR3 acts on the same axis but is not approved for human use.
Evidence at a glance
Each cell gives the kind of study and its source. The letter is the evidence level, not the result.
| Claimed effect | Humans | Animals | Cells |
|---|---|---|---|
| Visceral fat (HIV) | 412 and 806 people with HIV, 26 weeks: fell 15% (placebo +5%) [1]A; pooled treatment effect -15% [2]A | - | - |
| How long the effect lasts | Maintained for 52 weeks on continued treatment, fat reaccumulated after stopping [12]A | - | - |
| Liver fat (HIV) | 61 people with HIV, 12 months: fell 4.1 percentage points more than with placebo [3]A | - | - |
| Blood lipids | Triglycerides fell by 50 mg/dl over 26 weeks, rose by 9 mg/dl with placebo [1]A | - | - |
| Weight loss | Not indicated for weight loss, weight-neutral effect (label) [10]official | - | - |
| Healthy people and athletes | A two-week hormone study in 13 healthy men: growth hormone secretion and IGF-1 rose, insulin sensitivity did not change; benefit was not measured [14]B | - | - |
| Safety | Marked IGF-1 rise, fluid retention and glucose intolerance; long-term cardiovascular safety not established [10]official | - | - |
"-" = no such study is known.
What is tesamorelin used for?
In the United States tesamorelin is used to reduce excess abdominal fat in adults with HIV who have lipodystrophy [5]regulator [10]official. In the EU it has no approved use [4]regulator.
- Visceral fat in people with HIV: two phase 3 trials and their extensions [1, 2, 12]A.
- Fatty liver in people with HIV: one randomised trial, not an approved use [3]A.
Claims online. Weight loss and muscle building are not approved uses. According to the label, tesamorelin is not indicated for weight loss because its effect on weight is neutral [10]official. In August 2026 the FDA held that tesamorelin sold online as a "research peptide" was an unapproved drug [13]regulator.
How does tesamorelin work?
Tesamorelin makes the pituitary gland release the body's own growth hormone [4]regulator. Growth hormone plays a role in how fat tissue is formed and broken down [4]regulator.
IGF-1, a growth factor that carries many of growth hormone's effects, rises with it [9]E, not peer-reviewed. In the first phase 3 trial IGF-1 rose by 81% over 26 weeks [1]A.
Has tesamorelin been studied in humans?
Yes, but almost entirely in people with HIV [1, 2, 3]A. In other people there are only small studies, such as a two-week hormone study in 13 healthy men [14]B. We know of no published treatment study in athletes.
Human studies
- Phase 3 trial (2007). 412 people with HIV (86% men) who had accumulated abdominal fat received tesamorelin or placebo for 26 weeks. Visceral fat measured by CT fell by 15.2% with tesamorelin and rose by 5.0% with placebo. Triglycerides fell by 50 mg/dl and rose by 9 mg/dl with placebo [1]A.
- Extension (2008). After 26 weeks the tesamorelin group was re-randomised to continue treatment or switch to placebo. In those who continued, the reduction in visceral fat was maintained to 52 weeks (about 18%), but in those who stopped the fat reaccumulated [12]A.
- Pooled analysis of two trials (2010). In 806 people with HIV, visceral fat fell by 15.4% relative to placebo at 26 weeks, while fat under the skin of the abdomen did not change significantly [2]A.
- Fatty liver (2019). 61 people with HIV and fatty liver received tesamorelin or placebo for 12 months. Liver fat fell 4.1 percentage points more with tesamorelin than with placebo, a relative fall of 37%. A liver fat level below the normal cut-off (under 5%) was reached by 35% of the tesamorelin group and 4% of the placebo group [3]A.
Who studies tesamorelin?
The tesamorelin phase 3 trials and their extensions were published by the multicentre group of Falutz and colleagues in 2007-2010 [1, 2, 12]A. The fatty liver trial (Stanley and colleagues, 2019) was a multicentre trial supported by funding from the US National Institutes of Health (NIH) [3]A.
Who wrote this page: the editorial team
This page was written by the Molecular Recovery editorial team. The draft was made with the help of AI, and the claims were checked against the sources (AI policy). The page has not been medically reviewed. How we work: About us.
What are the side effects of tesamorelin?
According to the tesamorelin US label, the most common harms (over 5%) are joint pain, injection site redness and itching, pain in the limbs, swelling of the limbs and muscle pain [10]official.
What users report. In the Reddit accounts we compiled (not research), 58 of 70 people (83%) reported some harm, most often: injection site reaction (16, 23%), water retention or swelling (15, 21%) and allergic reaction, hives or rash (13, 19%). People tend to post when something goes wrong, so this share does not tell how common harms are. 40 of 70 people (57%) used other substances at the same time, most often ipamorelin (21), retatrutide (16) and GHK-Cu (9). So the reported fat loss cannot be attributed to tesamorelin. The harms in detail: Tesamorelin user experiences.
Warnings in the label
- Raised IGF-1. During 26 weeks of treatment IGF-1 rose above 2 standard deviation scores in 47% and above 3 in 36%. The effects of prolonged IGF-1 elevation are unknown [10]official.
- Fluid retention. May cause swelling, joint pain and carpal tunnel syndrome [10]official.
- Glucose metabolism. May cause glucose intolerance or diabetes [10]official.
- Hypersensitivity. Hypersensitivity reactions such as itching, redness and hives occurred in 4% [10]official.
- Cancer and pregnancy. Not used in active cancer or during pregnancy [10]official.
What the trials found
In the first phase 3 trial, adverse events did not differ significantly between groups, but more people in the tesamorelin group withdrew because of an adverse event [1]A. In the fatty liver trial, the tesamorelin group had more injection site complaints, none judged serious [3]A. No meaningful changes in blood glucose were seen in these trials [1, 2, 3, 12]A.
The EMA's medicines committee considered the rise in IGF-1 a major safety concern, because high IGF-1 may be linked to a higher cancer risk and worsening of diabetic eye disease. No long-term safety data were provided [4]regulator. More: Side effects and safety.
Interactions and who has no data
According to the label, the growth hormone raised by tesamorelin may change the clearance of drugs broken down by the liver's CYP450 enzymes, such as corticosteroids, sex steroids, anticonvulsants and ciclosporin. People on glucocorticoid replacement may need a higher dose [10]official.
Tesamorelin is contraindicated in pregnancy, and people with HIV are advised not to breastfeed [10]official. The treatment trials were in people with HIV [1, 2, 3]A, so they give no information on other groups.
Evidence against and what is unknown
The fat reduction is well measured, but its health benefit has not been shown. For this reason the EU medicines committee did not consider the product approvable [4]regulator.
Evidence against
- According to the EMA's medicines committee, the reduction in abdominal fat had not been shown to bring a clinically meaningful health benefit, and the trial patients did not represent European HIV patients, who on average have a lower BMI and less abdominal fat [4]regulator.
- The effect lasts only during treatment: when treatment stopped, visceral fat reaccumulated [12]A.
- Fat under the skin of the abdomen did not change significantly [2]A, and according to the label the effect on weight is neutral [10]official.
What the evidence does not support
- "Tesamorelin makes you lose weight": according to the label it is not indicated for weight loss [10]official.
- "It works in healthy people and athletes": nearly all trials of benefit were in people with HIV [1, 2, 3]A. In healthy men there is only a short hormone study [14]B.
- "Tesamorelin sold online is the same as Egrifta": the FDA held that tesamorelin sold online as a research peptide was an unapproved drug [13]regulator, and according to Fimea there is no reliable information on the content of such products [6]regulator.
What is not known
- Long-term cardiovascular safety: not established [10]official.
- The effects of prolonged IGF-1 elevation: unknown [10]official.
Tesamorelin dosage in studies
In the United States tesamorelin has an approved dosage for excess abdominal fat in people with HIV; in the EU there is no approved dosage [4]regulator. The label dose is 1.28 mg for Egrifta WR and 1.4 mg for Egrifta SV, under the skin once a day [10, 11]official. The two products are not substitutable [10]official. The dose is set by the prescriber, and this is not dosing advice.
| Study | Who | Dose and route | Duration |
|---|---|---|---|
| Phase 3 (2007) | 412 people with HIV and abdominal fat | 2 mg under the skin once a day | 26 weeks [1]A |
| Extension (2008) | people with HIV, re-randomised to continue or to placebo | 2 mg under the skin once a day | 52 weeks in total [12]A |
| Pooled analysis (2010) | 806 people with HIV | 2 mg under the skin once a day | 26-52 weeks [2]A |
| Fatty liver (2019) | 61 people with HIV and fatty liver | 2 mg under the skin once a day | 12 months [3]A |
What the figures do not tell you. The 2 mg in the trials was given with the old formulation. According to the label, 1.28 mg of Egrifta WR gives similar exposure, so milligrams are not comparable between products [10]official. Everyone studied had HIV [1, 2, 3]A, and the figures say nothing about other people.
More detail: Approved tesamorelin dosing. The calculator does not open with tesamorelin preselected, because the approved medicine is used as its product information says. The general calculator's list includes tesamorelin only to fill in the vial size of powder sold online, which is not the approved medicine Egrifta: Dose calculator.
Combinations and blends
We know of no study of tesamorelin combined with other peptides. Online sellers offer, for example, a blend of tesamorelin and ipamorelin, which the FDA held to be an unapproved drug in August 2026 [13]regulator. More: Ipamorelin and Peptide blends: what is in the vial and why the seller's label is not enough.
Tesamorelin is often compared with AOD-9604, which has no marketing authorisation and no published efficacy results in humans: approved or not: AOD-9604.
Status in the United States
The FDA approved Egrifta (tesamorelin) in November 2010 [5]regulator. The current products Egrifta WR and Egrifta SV are approved to reduce excess abdominal fat in adults with HIV who have lipodystrophy. They are not indicated for weight loss, and long-term cardiovascular safety has not been established [10, 11]official.
On 24 Aug 2026 the FDA sent a warning letter to an online seller whose products included tesamorelin and a tesamorelin and ipamorelin blend. According to the FDA, the products were unapproved drugs even though their labels said they were not intended for humans [13]regulator.
Is tesamorelin legal in Finland?
Tesamorelin is a medicine in Finland, but there is no authorised product [7]regulator [9]E, not peer-reviewed.
- Medicines list. Tesamorelin is in Annex 1 of Fimea's medicines list (decision 230/2025). Annex 1 substances are controlled as medicines in Finland [7]regulator.
- Marketing authorisation. In the EU the application was withdrawn on 21 June 2012, when the EMA's medicines committee was of the provisional opinion that the benefits did not outweigh the risks [4]regulator. According to Dopinglinkki, a Finnish information service on doping, there is no authorised product in Finland [9]E, not peer-reviewed.
- Ordering from abroad. According to Dopinglinkki, ordering growth hormone-releasing substances from abroad for personal use may be a medicines offence [9]E, not peer-reviewed.
- Fimea warning of 29 June 2026. Fimea warned about injectable peptides bought online and sold as "for research use only", and advises buying medicines only from legal pharmacies [6]regulator. More: Peptides and the law in Finland and Travelling with peptides.
This is not legal advice. Disclaimer.
Is tesamorelin doping?
Yes. The WADA 2026 Prohibited List names tesamorelin among growth hormone releasing factors in class S2.2.4, so it is banned in competitive sport [8]regulator.
How to assess a tesamorelin product
Because there is no authorised tesamorelin product in the EU, a product offered online is not under medicines supervision. According to Fimea, there is no reliable information on the content, quality and safety of such products, and in injectables impurities such as endotoxins can cause serious harm [6]regulator.
"For research use only" means the product is not intended for humans [6]regulator. A seller's own certificate of analysis (COA) does not by itself prove purity or content. More: How to read a COA and check a test result.
FAQ
Is tesamorelin an approved medicine?
In the United States, yes, to reduce excess abdominal fat in people with HIV [5]regulator [10]official. In the EU, no: the application was withdrawn in 2012 [4]regulator.
Does tesamorelin cause weight loss?
It is not meant for that. In people with HIV it reduced visceral fat [1, 2]A, but according to the label its effect on weight is neutral and it is not indicated for weight loss [10]official.
What side effects does tesamorelin have?
Common ones are joint and muscle pain, swelling and injection site symptoms [10]official. The rise in IGF-1 is a key safety concern [4]regulator [10]official.
Does the effect last after treatment?
No. When treatment stopped, visceral fat reaccumulated [12]A.
What is the dose of tesamorelin?
In the US labels the dose is 1.28 mg for Egrifta WR and 1.4 mg for Egrifta SV once a day; the trials used 2 mg of the old formulation [1]A [10, 11]official. The dose is set by the prescriber. More: Tesamorelin dosage in studies.
Is tesamorelin legal in Finland?
It is in Annex 1 of the Finnish medicines list, so it is controlled as a medicine [7]regulator, but there is no authorised product, and ordering it from abroad may be a medicines offence [9]E, not peer-reviewed. This is not legal advice.
Is tesamorelin banned in sport?
Yes. The WADA Prohibited List names it among growth hormone releasing factors in class S2.2.4 [8]regulator.
What do users themselves report about tesamorelin?
In the Reddit accounts of 70 people we compiled (not research), 16 (23%) reported some benefit and 58 (83%) some harm. The accounts are self-selected and prove neither that it works nor that it is safe: Tesamorelin user experiences.
Read the research yourself: sources
Every source opens the original publication or the regulator's page. The level shows what the source itself reports.
- Falutz J, et al. Metabolic effects of a growth hormone-releasing factor in patients with HIV. N Engl J Med. 2007;357:2359-2370. PMID 18057338 A
- Falutz J, et al. Effects of tesamorelin (TH9507) in HIV-infected patients with excess abdominal fat: a pooled analysis of two multicenter, double-blind placebo-controlled phase 3 trials with safety extension data. J Clin Endocrinol Metab. 2010;95:4291-4304. PMID 20554713 A
- Stanley TL, et al. Effects of tesamorelin on non-alcoholic fatty liver disease in HIV: a randomised, double-blind, multicentre trial. Lancet HIV. 2019;6:e821-e830. PMID 31611038 A
- European Medicines Agency. Egrifta (tesamorelin): withdrawal of the marketing authorisation application, questions and answers (EMA/CHMP/475021/2012). EMA regulator
- U.S. Food and Drug Administration. Drugs@FDA: BLA 022505 Egrifta (tesamorelin), approval history and labels, including Egrifta WR prescribing information (revised 3/2025). FDA regulator
- Fimea. Fimea warns: do not use injectable peptides purchased online (29 Jun 2026). Fimea regulator
- Finland. Lääkeluettelo (Fimea medicines list), 230/2025, annex 1. Finlex regulator
- World Anti-Doping Agency. 2026 Prohibited List, S2.2.4 Growth hormone releasing factors. WADA regulator
- Dopinglinkki. Ibutamoreeni (MK-677) ja muut kasvuhormonin vapauttajat (7 Nov 2025). Dopinglinkki E, not peer-reviewed
- U.S. Food and Drug Administration / DailyMed. Egrifta WR (tesamorelin) for injection, prescribing information. Revised 3/2025. DailyMed official
- U.S. Food and Drug Administration / DailyMed. Egrifta SV (tesamorelin) for injection, prescribing information. Revised 3/2024. DailyMed official
- Falutz J, et al. Long-term safety and effects of tesamorelin, a growth hormone-releasing factor analogue, in HIV patients with abdominal fat accumulation. AIDS. 2008;22:1719-1728. PMID 18690162 A
- U.S. Food and Drug Administration. Warning letter to NuScience Peptides LLC, MARCS-CMS 733652 (24 Aug 2026). FDA regulator
- Stanley TL, Chen CY, Branch KL, Makimura H, Grinspoon SK. Effects of a growth hormone-releasing hormone analog on endogenous GH pulsatility and insulin sensitivity in healthy men. J Clin Endocrinol Metab. 2011;96:150-8. PMID 20943777 B
Research sources checked 13 Oct 2026. Regulator and registry sources checked 15 Sep to 13 Oct 2026.
Evidence levels: A = randomised human trial or meta-analysis · B = observational human study or case series · C = animal study · D = cell or laboratory study · E = not peer-reviewed · regulator = a regulator's assessment or decision, not research evidence. The marker official means official product information (summary of product characteristics or label); it is not research evidence. For a review, the level shows what kind of research the statement rests on. No level: statements that something has not been studied, reviews' interpretations, named hypotheses and the general rules in our certificate-of-analysis guide.
Content is general information about research, not medical advice. If you have symptoms, contact a healthcare professional.