Everything researchers need: mechanism, FDA approval context, dosage protocol, side effects, and current COA-verified vendor pricing.
Research context only. Tesamorelin is FDA-approved for HIV-associated lipodystrophy only. All other use is off-label. This is not medical advice.
Tesamorelin (brand name Egrifta) is a synthetic analog of Growth Hormone Releasing Hormone (GHRH) developed by Theratechnologies. It is the only GHRH peptide with FDA approval, granted in 2010 for reducing excess visceral fat in HIV-positive adults with antiretroviral-associated lipodystrophy.
Unlike exogenous growth hormone injections, tesamorelin stimulates the pituitary to produce GH endogenously — preserving the natural feedback loop via somatostatin. The result is pulsatile GH release that mirrors physiological patterns rather than a sustained supraphysiological elevation.
Tesamorelin is a stabilized analog of the 44-amino acid GHRH peptide naturally secreted by the hypothalamus. Natural GHRH is rapidly degraded by endogenous dipeptidyl peptidase IV (DPP-IV) — tesamorelin's structural modification (a trans-3-hexenoic acid group at the N-terminus) protects it from this degradation, extending its effective activity window.
When injected subcutaneously, tesamorelin binds to GHRH receptors on somatotroph cells in the anterior pituitary. This triggers a pulse of growth hormone secretion that elevates serum GH and subsequently IGF-1 levels. Because somatostatin feedback remains intact, the system self-regulates — preventing runaway GH elevation.
The feedback advantage: Exogenous GH bypasses hypothalamic-pituitary regulation entirely. Sustained supraphysiological GH levels suppress endogenous production. Tesamorelin's approach preserves the axis — a key reason researchers and some clinicians prefer GHRH peptides over direct GH administration for long-term use.
Elevated IGF-1 is the primary mediator of tesamorelin's body composition effects. IGF-1 promotes lipolysis (fat breakdown) particularly in visceral adipose tissue, supports lean mass preservation, and has favorable effects on insulin sensitivity at physiological levels.
Two pivotal Phase 3 randomized controlled trials (LIPO-010 and LIPO-011) enrolled over 800 HIV-positive adults with abdominal lipodystrophy. Both trials used 2mg daily subcutaneous injections for 26 weeks with MRI/CT measurement of visceral adipose tissue (VAT) as the primary endpoint.
| Outcome | Tesamorelin 2mg | Placebo |
|---|---|---|
| VAT reduction | ~15% decrease | ~5% increase |
| Trunk fat change | Significant reduction | No change |
| Lean mass | Preserved | Preserved |
| Triglycerides | Modest improvement | No change |
| IGF-1 levels | ~100–150% increase | No change |
A separate body of research (Friedman et al., JAMA 2013) studied tesamorelin in older adults without HIV and found improvements in verbal memory and executive function. The proposed mechanism is GH/IGF-1's neuroprotective effects and support for hippocampal function. This has generated significant interest in tesamorelin beyond its FDA-approved indication.
Smaller studies and case series in non-HIV populations have reported results consistent with the mechanism — visceral fat reduction, lean mass preservation, and improved metabolic markers — though no Phase 3 trial has been conducted outside the HIV-lipodystrophy indication.
| Parameter | Value | Notes |
|---|---|---|
| Standard dose | 1–2mg daily | FDA-approved clinical dose is 2mg; some research protocols use 1mg |
| Timing | Fasted, before bed | Aligns with natural overnight GH pulse; insulin blunts GH release |
| Administration | Subcutaneous injection | Abdomen preferred; rotate sites each injection |
| Cycle length | 12–26 weeks | Clinical trials used 26 weeks; research protocols often 12–20 weeks |
| Reconstitution | 1–2mL BAC water per vial | Inject BAC water slowly down vial side; swirl gently, never shake |
| Storage | Refrigerate after reconstitution | Lyophilized: freeze or refrigerate. Reconstituted: 2–8°C, use within 3–4 weeks |
Stack context: Tesamorelin is commonly researched alongside GHRPs (ipamorelin) for synergistic GH stimulation via complementary receptors, and alongside GLP-1 peptides like retatrutide in body composition protocols (the "Recomp Stack"). Avoid combining with exogenous GH, which would override the feedback benefits that make tesamorelin's approach advantageous.
Tesamorelin has the most thoroughly documented safety profile of any GHRH peptide, owing to its Phase 3 trials and ongoing post-market surveillance as Egrifta.
| Side Effect | Frequency | Notes |
|---|---|---|
| Injection site reactions | Common (~25%) | Redness, swelling, bruising at injection site; typically mild |
| Peripheral edema | Common (~10–15%) | Fluid retention in extremities; usually transient |
| Arthralgia / joint pain | Common (~10%) | GH-class side effect; dose-dependent |
| Myalgia | Occasional | Muscle aches; resolves with dose adjustment or cycling |
| Glucose elevation | Occasional | GH-related insulin resistance; monitor in metabolic/pre-diabetic patients |
| Carpal tunnel symptoms | Occasional | Fluid retention compressing median nerve; resolves on discontinuation |
| Nausea | Occasional | Less common than GLP-1 class; mild when present |
Contraindications from the clinical trials: active malignancy, disruption of the hypothalamic-pituitary axis (from tumor, surgery, or radiation), pregnancy, and hypersensitivity to tesamorelin or mannitol (an excipient in Egrifta).
Tesamorelin is available as a research peptide from COA-verified suppliers. Current pricing from our tracked vendors:
Live-tracked pricing from S1 Research, Tegridy Research, and AMP — with promo codes.
View Tesamorelin Pricing → Dosage Calculator