GH secretagogue

Hexarelin

Controlled trials

Synthetic hexapeptide ghrelin receptor (GHS-R1a) agonist and one of the most potent GH secretagogues studied in humans, with additional cardiac data.

SubQIMAdvancedNot approved anywheremuscle growthrecovery and sleepinjury repairfat loss

Also known as Examorelin · Hexarelin acetate

At a glance

Dose summary

Typical dose100 mcg
Range50 mcg–200 mcg
FrequencyDaily
Half-life~1 h
ScheduleOnce daily
Cycle length4 weeks
RouteSubQ · IM
Experience levelAdvanced
Evidence gradeControlled trials
ApprovalNot approved anywhere
Where the dose comes fromCommunity practice, not a trial

No regulator and no trial set these numbers. They describe what people actually do, recorded so you can see the range rather than guess at it — which is not the same thing as a recommendation.

Reconstitution

What to draw, at the usual vial

A 2 mg vial reconstituted with 2 mL of bacteriostatic water gives 1.00 mg/mL. A typical 100 mcg dose is 0.100 mL — pull the plunger to 10 units on a U-100 syringe.

Concentration1.00 mg/mL
Draw volume0.100 mL
U-100 units10 units
Doses per vial20

Same dose, other vial sizes

VialWaterConcentrationDrawUnitsDoses
2 mg2 mL1.00 mg/mL0.100 mL10 units20
5 mg2 mL2.50 mg/mL0.040 mL4 units50

The highlighted row is the one quoted above: the smallest listed vial that holds at least four typical doses. Change any of it — a different vial, more or less water, a different dose — on the reconstitution calculator, which draws the syringe to true U-100 graduations.

Mechanism & evidence

What it is, and what is known

Synthetic hexapeptide ghrelin receptor (GHS-R1a) agonist and one of the most potent GH secretagogues studied in humans, with additional cardiac data. Its defining practical problem is tachyphylaxis: repeated dosing blunts the GH response over roughly two to four weeks, which is why it is cycled short rather than run continuously. It also lacks the selectivity of ipamorelin, so prolactin and cortisol elevation are expected at higher doses.

The caveat

Well studied as a GH secretagogue, but tachyphylaxis blunts it within weeks.

Tolerability

Reported side effects

  • Marked receptor desensitisation — the GH response falls off within a few weeks of continuous daily use, so cycles are kept short with washout periods
  • Raises prolactin and cortisol more than ipamorelin does
  • Strong hunger spike within 20 to 30 minutes of dosing
  • Water retention, puffiness and numb or tingling hands
  • Head rush, flushing or transient light-headedness after injection
  • Injection site irritation

Hard stops

Do not use this if

  • Pregnancy, possible pregnancy, or breastfeeding
  • Active, suspected or recently treated malignancy
  • Under 18

These are flags, not a screening. They do not replace a conversation with a clinician who knows your history.

Handling

Storage

Sealed powder, refrigerated24 months
After reconstitution, refrigerated28 days

Keep it cold, keep it dark, and label the vial with the date you mixed it. Discard anything cloudy or past the window above.

Combinations

Commonly stacked with

Stacking multiplies the side-effect surface and makes it impossible to tell which compound did what. Add one thing at a time.

References

Sources

Educational information only, not medical advice. Talk to a licensed clinician before starting, changing, or stopping anything.