Tesamorelin

Mechanism of Action

A synthetic analogue of the full 44-amino-acid human growth hormone releasing factor, with a hexenoyl group on the N-terminus that slows enzymatic degradation. It binds pituitary GHRH receptors to restore pulsatile growth hormone secretion, raising IGF-1 and shifting adipose metabolism preferentially against visceral rather than subcutaneous fat.

Typical Protocol

Educational reference only — not medical advice.

Pharmacokinetics & Dosing Rationale

Tesamorelin is administered subcutaneous injection with an approximate systemic half-life of ~26 minutes in plasma; the growth hormone rise it triggers persists 4-6 hours. Steady-state and tissue-level effects can outlast plasma concentration, which is why dosing frequency (Once daily) is designed to match receptor kinetics rather than plasma exposure. A synthetic analogue of the full 44-amino-acid human growth hormone releasing factor, with a hexenoyl group on the N-terminus that slows enzymatic degradation. It binds pituitary GHRH receptors to restore pulsatile growth hormone secretion, raising IGF-1 and shifting adipose metabolism preferentially against visceral rather than subcutaneous fat.

How to Administer

1. Route: Subcutaneous injection. Typical starting dose 2 mg (1.28 mg for the newer F8/WR formulation), Once daily.
2. Timing: Bedtime, to sit with the natural overnight GH pulse — keep it the same each dosing day to make effects legible.
3. Cycle length: 26 weeks in the pivotal trials; benefit reverses on stopping. Reassess with bloods and symptom logs before repeating.
4. Rotate sites across the abdomen (avoiding a 2 cm radius around the navel), outer thighs and flanks. Never inject through a bruise or mole.

Reconstitution & Injection Technique

1. Reconstitute lyophilised powder with bacteriostatic water (0.9% benzyl alcohol) — sterile water is acceptable but shortens shelf life to ~72 hours.
2. Typical dilution: add 2 mL of bacteriostatic water to a 5 mg vial → 2.5 mg/mL; a 10-unit insulin syringe mark = 0.25 mg.
3. Inject the diluent slowly against the vial wall — never onto the powder — and gently swirl. Do not shake; peptides denature under shear.
4. Once reconstituted, store upright in the refrigerator (2–8 °C) and use within 30 days.
5. Draw the dose with an insulin syringe (29–31G, 8 mm), swab the site with alcohol, pinch subcutaneous tissue on the abdomen or thigh, inject at 90°.

Sterile technique is not optional. Use a fresh needle for every injection.

Cycling & Stacking Strategy

• Standard protocol: 2 mg (1.28 mg for the newer F8/WR formulation), Once daily, for 26 weeks in the pivotal trials; benefit reverses on stopping.
• Ramp up: start at the lower end of the dose range for the first 7–10 days to gauge tolerance and side effects before titrating.
• Break periods let receptor sensitivity and endogenous feedback loops normalise — running back-to-back cycles without a wash-out erodes the effect.
• Common stack: Zone 2 cardio, Resistance training, Regular HbA1c and IGF-1 monitoring. Introduce one compound at a time so you can attribute effect and side effect.

Who This Is For

What to Monitor

Reported Benefits

• 15-18% reduction in visceral adipose tissue versus placebo in phase 3 trials
• Improved triglycerides and cholesterol alongside the fat loss
• Raises IGF-1 without the supraphysiological spikes of exogenous growth hormone
• Does not reduce subcutaneous fat, which is metabolically less harmful

Safety Profile

Common Mistakes

• Chasing a bigger dose instead of consistency — Tesamorelin outcomes track cumulative exposure, not peak concentration.
• Skipping baseline bloods, so there is no way to know whether the cycle actually moved a biomarker.
• Stacking three or four novel compounds at once — you lose the ability to attribute any effect or side effect.
• Ignoring the training, sleep and nutrition fundamentals that are prerequisites for every peptide protocol.
• Reusing insulin needles or failing to rotate injection sites — a preventable cause of local reactions and lipohypertrophy.
• Injecting immediately after a meal — insulin blunts the GH pulse. Fasted, pre-bed dosing is the point.

Evidence Grade — A

Grade A — supported by multiple randomised human trials or an approved regulatory indication. Mechanism, dosing and safety are well characterised in humans.

Below are the primary references used to grade Tesamorelin. Follow the links for full-text where available and cross-check against the current literature.

Frequently Asked Questions

References

1. [1]Effects of tesamorelin on visceral fat and liver fat in HIV-infected patients with abdominal fat accumulation: a randomized clinical trial — JAMA, 2014
2. [2]Tesamorelin, a growth hormone-releasing factor analogue, in HIV-infected patients with excess abdominal fat — New England Journal of Medicine, 2007

Further reading: Research library → · Protocols →