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Tesamorelin calculators

Reconstitution, dose, mg ↔ units, and vial duration — all four Tesamorelin calculators in one place, pre-filled with a 5 mg / 2 mL example.

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Tesamorelin is a daily injection people use specifically to reduce stubborn deep belly fat (visceral adipose tissue). It's an analog of growth hormone-releasing hormone (GHRH) that prompts the pituitary to release more of the body's own GH. In FDA trials for HIV-related lipodystrophy, daily 2 mg injections reduced visceral fat by about 15–18% over 26 weeks. This page covers reconstitution math and daily dose logging.

How the four Tesamorelin calculators connect

This tool turns the three numbers on your Tesamorelin vial into the only number that matters at injection time: how many units to draw on a U-100 insulin syringe. The math is one formula — concentration in mg per mL equals the milligrams of peptide in the vial divided by the milliliters of bacteriostatic water you add — and every other answer falls out of that.

In the worked example below, a 5 mg vial of Tesamorelin reconstituted with 2 mL of BAC water produces a concentration of 2.5 mg/mL. To draw the example dose of 1 mg from that vial you pull 0.40 mL — about 40 units on a standard insulin syringe. Change any input and the rest updates instantly so you can pre-plan a vial before you ever touch a needle.

Vial size, diluent volume, and dose are the three inputs that genuinely change the answer. Doses-per-vial is a derived output — it's the vial mg divided by the dose mg, rounded down. The most common edge case is a tiny dose: at very high concentration, a 0.1 mL draw is only a few units on the syringe, which is hard to read accurately. If your unit count drops below five, consider reconstituting the next vial with more BAC water so each dose covers a larger volume.

Use this calculator any time you open a fresh vial, switch BAC water volume, or step a titration dose up. Each new vial gets its own concentration and its own unit count — the previous vial's numbers do not carry over, and that is the single most common reconstitution mistake.

What the Tesamorelin calculators cover

Tesamorelin is the complete 44-amino-acid sequence of human growth hormone-releasing hormone (GHRH), uniquely modified at its N-terminus with a trans-3-hexenoyl group. This single structural addition is designed to shield the peptide from rapid enzymatic degradation by dipeptidyl peptidase-4 (DPP-IV), a key differentiator from other GHRH analogs. This protection results in a more sustained presence in plasma and a longer duration of action after administration. Consequently, its pharmacological profile and the protocols studied in literature differ significantly from shorter-lived compounds that target the same receptor.

Within the landscape of regulatory review, Tesamorelin holds a distinct position. It is the only GHRH analog that has secured and maintained FDA approval for a specific indication: the reduction of excess abdominal adiposity in HIV-infected individuals with lipodystrophy. This established history provides a substantial body of public data from clinical trials, delineating its parameters of use. The dose magnitudes documented in this research, often around 1 mg daily, are considerably larger than those for other peptides in its class, influencing everything from reconstitution strategy to administration technique.

Tesamorelin represents a significant modification of the endogenous growth hormone-releasing hormone (GHRH) peptide. It is a synthetic analog containing the full 44-amino-acid sequence of human GHRH, but with a crucial chemical addition. This addition, a trans-3-hexenoyl group attached to the N-terminus, is the defining structural feature of the molecule. Its purpose is to fortify the peptide against rapid enzymatic degradation, a primary limitation of administering native GHRH. This enhanced stability is central to how the peptide is studied and how its administration schedules are planned.

How Tesamorelin is studied

Tesamorelin functions by binding to and activating the growth hormone-releasing hormone receptor (GHRHR), located on somatotroph cells in the anterior pituitary gland. This is the identical pathway used by endogenous GHRH to stimulate the synthesis and pulsatile secretion of growth hormone. The critical distinction lies in its metabolic stability; while natural GHRH and unmodified analogs like sermorelin are quickly cleaved and inactivated by the enzyme dipeptidyl peptidase-4 (DPP-IV), Tesamorelin's trans-3-hexenoyl modification sterically hinders this process. This resistance to breakdown extends its plasma half-life, allowing for prolonged GHRHR stimulation from a single dose.

The primary mechanism differentiating tesamorelin from native GHRH lies in its resistance to enzymatic breakdown. Endogenous GHRH is rapidly inactivated by the enzyme dipeptidyl peptidase IV (DPP-IV), which cleaves the peptide bond between the first two amino acids, Tyr1 and Ala2. Tesamorelin is engineered to prevent this. The trans-3-hexenoyl moiety, a six-carbon acyl group, is covalently bonded to the N-terminal tyrosine. This chemical shield sterically hinders the DPP-IV enzyme, physically blocking its access to the cleavage site. This protection results in a substantially longer plasma half-life, enabling the molecule to circulate and interact with GHRH receptors in the pituitary for an extended duration.

How people log Tesamorelin

Protocols documented in published research on Tesamorelin typically involve a daily administration cadence, scheduled for seven days per week. The studied dose is substantial, frequently specified at 1 mg or 2 mg per day, which requires a much larger injection volume compared to GHRH fragments dosed in micrograms. For a 1 mg dose, drawing from a moderately concentrated vial requires careful measurement, often with a standard 1 mL U-100 insulin syringe to ensure accuracy for volumes that can be 40 units or more.

In a departure from the common evening schedule for many GH secretagogues, clinical trials for Tesamorelin predominantly utilized a morning-dosing schedule. The rationale is linked directly to its extended half-life; since the peptide provides a sustained GHRH signal, it is not necessary to time its administration to coincide with the primary natural growth hormone pulse during sleep. This morning administration pattern is a well-documented characteristic of the protocols established during its clinical development for its approved indication.

The structural stability of tesamorelin directly informs the administration schedules observed in research literature. Its resistance to DPP-IV degradation permits a daily dosing cadence, which allows for sustained engagement of the GHRH receptor. This contrasts sharply with native GHRH, which would require much more frequent administration to achieve a similar exposure profile. When planning documentation for a research project, this daily cadence is a key parameter to schedule and record. For calculation purposes, a 5 mg vial reconstituted with 2 mL of diluent contains 2.5 mg per mL. A 1 mg illustrative dose is therefore calculated as 0.4 mL or 40 units on a standard U-100 insulin syringe, often documented on a daily cadence.

Common Tesamorelin mistakes to avoid

  • Assuming the per-dose volume and syringe draw will be as small as sermorelin's and failing to plan for a larger subcutaneous injection.
  • Neglecting to systematically document and rotate injection sites, which can lead to localized lipohypertrophy that interrupts a planned daily schedule.
  • Mistaking the typical milligram (mg) dose for micrograms (mcg) in the calculator, leading to a thousand-fold dosing error.
  • Attempting to reconstitute a 5 mg vial with an excessively small diluent volume, making the large 1 mg dose difficult to measure and draw accurately.
  • Administering the daily dose in the evening by default, contrary to the morning administration schedule used in the vast majority of published clinical trials.
  • Mistaking the trans-3-hexenoyl modification for a simple carrier or delivery system, rather than the specific chemical shield it is.
  • Failing to distinctly log the molecule as tesamorelin, instead using the generic term 'GHRH', which obscures the critical stability difference in protocol review.
  • Neglecting to record whether the tracked material is the pharmaceutical product Egrifta or a research-grade compound, a distinction vital for data integrity.

Frequently asked questions about Tesamorelin

Why is the Tesamorelin dose in milligrams (mg) when other GHRH analogs are often dosed in micrograms (mcg)?
Tesamorelin's milligram-level dosing is a function of its molecular structure and the extensive clinical research that established its use profile. As the full 44-amino-acid GHRH sequence, its molecular weight and receptor affinity necessitate a larger mass to achieve the desired level of pituitary stimulation. The protocols for its FDA-approved indication were developed around a 1 mg or 2 mg daily dose, reflecting its distinct pharmacology compared to smaller, truncated peptide fragments.
What specifically is the purpose of the trans-3-hexenoyl group on Tesamorelin?
The trans-3-hexenoyl group is a fatty acid-based modification chemically bonded to the start of the peptide chain. Its sole purpose is to serve as a physical shield, sterically hindering the enzyme DPP-IV from accessing its cleavage site on the GHRH sequence. This protection from enzymatic degradation is what grants Tesamorelin a significantly longer half-life compared to native GHRH, which is its primary design advantage.
Using a 5 mg vial reconstituted with 2 mL of water, how many units would a 1 mg dose be?
When a 5 mg vial is reconstituted with 2 mL of bacteriostatic water, the solution's final concentration is 2.5 mg/mL. To obtain a 1 mg dose from this solution, you would need to draw 0.40 mL. On any standard U-100 insulin syringe, a volume of 0.40 mL is equivalent to exactly 40 units.
Why is tracking injection site rotation especially important for Tesamorelin?
The emphasis on site rotation is a direct consequence of its common protocol: daily administration combined with a relatively large dose volume. Delivering a volume of 0.4 mL (40 units) or more into the same subcutaneous tissue spot every day increases the risk of lipohypertrophy, a benign but palpable thickening of fat tissue. This can alter absorption rates and impact comfort, making the careful logging and rotation of sites an important variable to monitor for consistent administration.
Can Tesamorelin be considered a longer-lasting version of sermorelin?
While both peptides activate the GHRH receptor, they are fundamentally different molecules. Sermorelin represents only the first 29 amino acids of the GHRH sequence. Tesamorelin is the full 44-amino-acid sequence and includes an additional protective modification. This structural difference gives Tesamorelin a much longer half-life and leads to different studied protocols with larger dose magnitudes.
Why was Tesamorelin studied with morning, rather than evening, administration?
The morning administration schedule seen in most clinical literature is tied to Tesamorelin's extended half-life. Because it resists rapid breakdown and provides a prolonged GHRH signal for many hours, it does not need to be timed to coincide with the body's primary nocturnal growth hormone pulse. A morning dose provides a sustained level of GHRH receptor stimulation throughout the day, a profile that was extensively studied and established for its approved indication.
What is the concrete chemical difference between tesamorelin and native GHRH?
Tesamorelin is the full 44-amino-acid sequence of human GHRH with one specific chemical modification. A trans-3-hexenoyl group is covalently attached to the N-terminal tyrosine residue. This addition serves to protect the molecule from rapid degradation by the DPP-IV enzyme, which is what gives tesamorelin a significantly longer half-life compared to unmodified, endogenous GHRH.
What is the difference between Tesamorelin and Egrifta for logging purposes?
The active molecule is identical; tesamorelin is the generic name for the peptide, and Egrifta is the brand name for the FDA-approved pharmaceutical product. The key difference for logging is the source and standardization. Egrifta comes in a fixed-dose kit with verified purity, while material labeled as 'tesamorelin' is typically for research purposes and may have different purity and handling considerations. It is critical to document which form is being studied for accurate record-keeping.
Why is the DPP-IV enzyme unable to cleave tesamorelin?
The DPP-IV enzyme is prevented from cleaving tesamorelin due to steric hindrance. The enzyme's active site must physically access the peptide bond between the first and second amino acids (Tyr1-Ala2) to break it. The bulky trans-3-hexenoyl group attached at the N-terminus acts as a physical shield, blocking the enzyme's approach. This structural defense preserves the full-length peptide, allowing it to remain active in plasma for much longer.

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