Sermorelin: a dose per kilo, not per vial

The sermorelin reproduces the first 29 amino acids of GHRH, the hypothalamic hormone that tells the pituitary to release growth hormone. It is not growth hormone itself, and it is not tesamorelin, which reproduces all 44 amino acids of GHRH with another group. The two product pages remain separate. The general framework is in the guide HGH and tesamorelin.

Because it acts upstream, the surge it causes remains subject to the body's brakes, notably somatostatin. Raising the dose does not raise the response linearly. That is also why the dose is taken at bedtime, on an empty stomach: the largest natural growth hormone surge occurs in early sleep, and a recent meal, via insulin, slows it.

Two ways to read a dose

The former medicine Geref specified 30 µg/kg subcutaneously, once a day, at bedtime, in a paediatric setting. This quantity depends on weight. It cannot be read from a "5 mg" or "10 mg" label. Studies in adults have also used per-kilo doses, around 10 µg/kg in the evening, or higher fixed doses in short trials. These are not interchangeable calendars.

The catalogue page uses the fixed-dose research schedule, the one that can be measured on a syringe without knowing a weight:

• Weeks 1 to 2: 100 µg at bedtime.
• Weeks 3 to 4: 200 µg.
• Weeks 5 to 12: 300 µg.

It stops at 300 µg. Beyond that, the gain is not proportional, and it is not the step used here. The details are on the protocol sheet.

From the vial to the syringe mark

A 10 mg vial in 2 mL gives 5 mg/mL, i.e. 5,000 µg/mL.

• 100 µg = 0.02 mL = 2 U-100 units.
• 200 µg = 0.04 mL = 4 units.
• 300 µg = 0.06 mL = 6 units.

These volumes are small. For a more comfortable mark, reconstitute the vial in a little more solvent and redo the calculation. The 5 mg vial in 2 mL gives 2.5 mg/mL: the same doses take up twice the volume there. 10 mg in the vial is not "ten doses of 1 mg". Nor is it the schedule.

What it is not

Not ipamorelin, which acts on the ghrelin receptor, another release signal. Not tesamorelin, a 44-amino-acid analogue, whose medicine Egrifta has a schedule in milligrams, not micrograms. Not HGH, which bypasses the pituitary and is measured in international units. Mixing these pages means adding up doses that do not speak of the same thing.

The powder and the solution are kept between 2 and 8 °C. Write the reconstitution date. Do not shake: roll the vial between your palms until the lyophilizate has disappeared. A cloudy solution cannot be "rescued" by heating.

In the catalogue: 5 mg and 10 mg.