Growth hormone secretagogue
Tesamorelin
A stabilised growth-hormone-releasing hormone analogue approved for excess visceral fat in HIV-associated lipodystrophy — and for nothing else.
What it is
Tesamorelin is a 44-amino-acid analogue of growth-hormone-releasing hormone (GHRH) with a chemical cap that blocks the enzyme that would normally destroy it. It is an approved prescription medicine (Egrifta) for reducing excess visceral abdominal fat in adults with HIV-associated lipodystrophy. It is not approved for weight loss, bodybuilding or anti-ageing, and it is prohibited in sport.
How it works
- 1
Binds GHRH receptors in the pituitary, prompting the gland to release growth hormone in its natural pulsatile pattern.
- 2
Growth hormone then raises IGF-1, mainly produced in the liver.
- 3
Unlike continuous growth hormone exposure, pulsatile release favours fat mobilisation over fluid retention.
- 4
Visceral fat — the fat around internal organs — falls preferentially, while subcutaneous fat changes little.
What it's studied for
Reported and studied effects
- Roughly 15–18% reduction in visceral adipose tissue at 26–52 weeks in randomised trials
- Sustained rises in IGF-1
- Reduced liver fat in a subset of participants
- Little change in subcutaneous fat or total body weight
- Improved triglyceride levels in some trials
Research protocol notes
Research context onlyResearch context only — dosing is set by the prescribing physician. Trials used 2 mg subcutaneously once daily for 26–52 weeks, with IGF-1 monitored periodically. This is not a weight-loss protocol and it is not a general-purpose GH protocol.
These figures are described so you can understand what researchers did. They are not a dose, a schedule, or a suggestion — and they are not a substitute for a doctor.
Possible side effects and contraindications
Safety profile
Possible side effects
- Injection-site reactions, sometimes with nodules or bleeding
- Joint pain and peripheral swelling
- Carpal tunnel symptoms
- Raised IGF-1, which requires monitoring
- Possible effects on blood glucose
- Theoretical concern about growth promotion in existing tumours with sustained GH and IGF-1 elevation
Contraindications and cautions
- Active malignancy
- Pregnancy and breastfeeding
- Hypersensitivity to tesamorelin or its excipients
- Disrupted pituitary anatomy or hypopituitarism requires specialist assessment
- Preexisting carpal tunnel syndrome should be discussed with a doctor
A side-effect list is never complete, and these are not the only situations that warrant caution. Anything unexpected, or anything you are unsure about, should be discussed with a doctor before use.
Evidence assessment
Several randomised controlled trials with imaging-based fat endpoints supported regulatory approval, but the evidence is concentrated in one population (HIV lipodystrophy) and covers relatively short durations.
References
- 01Falutz et al., Metabolic Effects of a Growth Hormone–Releasing Factor in Patients with HIV, NEJM 2007
- 02US Food and Drug Administration — Egrifta (tesamorelin) prescribing information
- 03Tesamorelin visceral adipose tissue trials — PubMed literature search
References link to published literature, regulator pages or literature indexes. Where a link points to a search, it collects the peer-reviewed work on that molecule rather than a single study.
Related
Related peptides
Other entries in Growth hormone secretagogue.
Growth hormone secretagogue
CJC-1295
A modified growth-hormone-releasing hormone analogue whose albumin binding gives it an unusually long action. Studied in small human trials; not an approved medicine.
Growth hormone secretagogue
CJC-1295 (no DAC) + Ipamorelin blend
The classic growth-hormone stack in one vial: a GHRH fragment with a secretagogue, unapproved and prohibited in sport.
Growth hormone secretagogue
CJC-1295 (no DAC) / mod GRF 1-29
The short-acting sister of CJC-1295: a GHRH fragment that produces brief growth-hormone pulses instead of sustained elevation.