Sermorelin: GHRH Analogue Research, Uses and PH Status

Abstract still life: a chain of twenty-nine small pale glass beads laid in a gentle curve on stone — **Sermorelin.** Illustration, not a product photo.

Research compound. Not approved by FDA Philippines for human use unless stated. Nothing here is a dosing recommendation or medical advice.

What it is

Sermorelin is a synthetic copy of the first 29 amino acids of growth hormone-releasing hormone (GHRH), the hypothalamic signal that tells the pituitary gland to release growth hormone. Those 29 residues carry the full biological activity of the 44 amino acid natural hormone, which is why the fragment works on its own.

It is one of the few compounds in this library that was once an approved medicine. Serono sold it as Geref, used to test pituitary function and to treat growth hormone deficiency in children. The product left the US market in 2008.

How it works

Sermorelin binds the GHRH receptor on somatotroph cells in the anterior pituitary. That triggers a pulse of growth hormone, which in turn drives the liver to make IGF-1.

Two features separate it from taking growth hormone directly:

The feedback loop stays intact. Somatostatin, the brake on GH release, still works. The pituitary cannot be pushed far past its own ceiling, which researchers have argued makes overdosing harder than with somatropin.
Release is pulsatile. Natural GH comes in bursts, mostly during deep sleep. Sermorelin produces a burst rather than the flat, sustained level that a GH injection gives. This is why study protocols dosed it at night.

The trade-off is its very short life in the blood. Enzymes cut the unmodified fragment within minutes. CJC-1295 and tesamorelin are both later attempts to fix that.

What the research found

The best-known human work comes from ageing studies in the 1990s, run to test whether restoring youthful GH pulses could reverse some age-related decline.

Vittone and colleagues (1997) gave healthy men aged 64 to 76 a nightly injection for six weeks. GH secretion and IGF-1 rose, confirming the pituitary of older men still responds to GHRH.
Khorram and colleagues (1997) ran a 16-week study in men and women aged 55 to 71 using a closely related GHRH (1-29) analogue. IGF-1 rose in both sexes. Men showed an increase in lean body mass and improved insulin sensitivity; the changes in women were smaller.
A companion paper from the same group reported shifts in immune markers over the same period.

These were small trials of weeks to months. None measured hard outcomes such as fractures, disease or survival.

Side effects reported in studies

The ageing and paediatric literature describes injection-site reactions (pain, redness, swelling) as the most common event, along with facial flushing, headache and occasional dizziness. Because any GH-raising compound increases IGF-1, the theoretical long-term concerns are the same as for growth hormone itself: fluid retention, joint aches, reduced insulin sensitivity, and the open question of IGF-1 and cancer risk.

Sermorelin vs other GH secretagogues

Compound	Type	Half-life	Notes
Sermorelin	GHRH fragment	Minutes	Unmodified, once approved
CJC-1295 no DAC	Modified GHRH	No published human data	Substitutions resist enzyme breakdown
CJC-1295 with DAC	Modified GHRH + albumin anchor	Days	Continuous rather than pulsed signal
Tesamorelin	Modified GHRH	About 30 minutes	FDA-approved for HIV-associated visceral fat
Ipamorelin	Ghrelin mimetic	About 2 hours	Different receptor; often paired with a GHRH

Status in the Philippines

No sermorelin product is registered with FDA Philippines, so it cannot be sold as a medicine. It is not a controlled substance under RA 9165. Local availability is through research-chemical suppliers, where it is less common than CJC-1295 and ipamorelin.

Storage

Lyophilised powder is stable at room temperature for short periods but is best kept refrigerated. Once mixed with bacteriostatic water, keep it at 2 to 8°C and away from the freezer door. See the beginner guide for handling basics.

Doses used in published research

What investigators actually administered, as reported in the cited study. This is a record of the literature, not a recommendation.

Study	Population	Regimen
Vittone et al., Metabolism 1997	Healthy men aged 64 to 76	2 mg subcutaneous, once nightly, 6 weeks
Khorram et al., J Clin Endocrinol Metab 1997	Men and women aged 55 to 71	10 mcg/kg of a GHRH (1-29) analogue, subcutaneous nightly, 16 weeks after 4 weeks placebo

Common questions

Is sermorelin the same as HGH?

No. Sermorelin is a signal that asks the pituitary to release its own growth hormone. HGH (somatropin) is the hormone itself. Because sermorelin works through the pituitary, the body's negative feedback via somatostatin still applies.

Why was sermorelin withdrawn in the US?

The branded product Geref was discontinued in 2008 for manufacturing reasons, not because of a safety finding. Compounding pharmacies in the US continued to prepare it for years afterwards.

Is sermorelin legal in the Philippines?

It is not a scheduled controlled substance, but no sermorelin product is registered with FDA Philippines. It is sold locally as a research compound, not as a medicine.

How is sermorelin different from CJC-1295?

CJC-1295 is a modified GHRH (1-29) with amino acid substitutions that resist breakdown, and in the DAC version a chemical anchor that binds albumin for a half-life measured in days. Sermorelin is the unmodified fragment and clears in minutes.