What Is Tesamorelin? Dosage, Half-Life & How to Track It

What Tesamorelin is and how it works

Tesamorelin is a synthetic 44-amino-acid peptide — essentially the full-length GHRH molecule with a chemical modification (a trans-3-hexenoic acid group) that protects it from being broken down by the enzyme DPP-4. That stabilization is what lets it survive long enough in the body to work reliably at a once-daily dose, unlike shorter, faster-cleared GHRH fragments like sermorelin.

It binds the same GHRH receptor on the pituitary as sermorelin and CJC-1295, prompting a natural, pulsatile release of growth hormone and a downstream rise in IGF-1. The clinical case for it is unusually strong for a peptide in this category: it is FDA-approved (brand name Egrifta, later reformulated as Egrifta SV) specifically for reducing excess visceral abdominal fat in people with HIV-associated lipodystrophy.

Outside that approved indication, it is studied and used off-label for GH/IGF-1 support, body composition, and — because visceral fat reduction was its headline clinical result — general metabolic goals. As with the other GHRH analogs, its effect depends on a responsive pituitary and is often paired with a GHRP for a stronger combined pulse.

Typical dosing & reconstitution

Tesamorelin is reconstituted from lyophilized powder with bacteriostatic water. The FDA-approved regimen is 2 mg subcutaneously once daily, in the evening; many protocols start with a 1 mg titration week to check tolerability before moving to the full dose.

Reconstitution volume varies by vial size, and it changes the concentration meaningfully:

At 2.0 mg/mL, the standard 2 mg dose is a full 100-unit (1.00 mL) injection — right at the top of a standard insulin syringe. A more concentrated reconstitution (the 20 mg vial in 3 mL) brings that same 2 mg dose down to 30 units, which is exactly what the reconstitution calculator is built to compare.

Half-life & what it means for frequency

Tesamorelin’s half-life is short — roughly 26 to 38 minutes per its FDA prescribing information — despite the stabilization that protects it from rapid enzymatic breakdown. That is still long enough to reliably trigger a GH pulse once daily, which is the approved and standard schedule.

Evening dosing is the norm, timed to work with the body’s natural nocturnal GH rhythm rather than against it. As with the other short-half-life peptides in this family, there is no depot effect — a missed dose does not carry forward, and consistency matters more than any single injection.

What to track & common side effects

In its FDA trials, the most common side effects were injection-site reactions (redness, itching, or bruising), joint pain or stiffness (arthralgia), and — because it raises IGF-1 — some fluid retention, especially early in treatment. Because it raises GH/IGF-1, people with active malignancy are generally advised against it, and blood-sugar effects are worth monitoring given GH’s effect on insulin sensitivity.

Worth tracking: the daily injection itself, any joint or swelling symptoms (common enough to watch for), and — since visceral fat is its best-studied effect — waist circumference or body composition over time, alongside IGF-1 if you lab it.

Frequently asked questions