Other GH-releasing peptides (GHRP-1, GHRP-4, GHRP-5, alexamorelin)

GHRP1, GHRP4, GHRP5, Growth hormone-releasing peptide-1

Growth hormone & secretagoguesNot approved for humansWADA S2 · prohibitedEvidence: limited human data

Four lesser-known synthetic GH-releasing peptides (ghrelin-receptor agonists) from the same family as GHRP-6 and hexarelin. Human data are limited to single doses or absent.

What it gives

What people use it for and what the sources report. Strength is a general category from the literature: mild, clear or strong.

Purpose

Never approved. In sport: sold online as 'research peptides' and used, like GHRP-2 and GHRP-6, to raise GH for muscle, fat loss and recovery; none of these benefits has been studied in people.

What people seek and what studies show

Used to raise GH. A single dose of GHRP-1 raised GH in short but healthy children and teenagers, with a brief cortisol rise and no prolactin change. In six young adults alexamorelin released as much GH and prolactin as hexarelin, more ACTH and cortisol at the higher dose, and raised aldosterone. GHRP-4 and GHRP-5 were never studied in people. No study measured muscle, fat or recovery.

Effects

Recovery

Evidence: Limited human data — some human studies, small or short

Sought effects by goal (as reported)

Mass
Sought for: recovery
Strength
Sought for: recovery
Endurance
Sought for: recovery
Recovery & healing
Sought for: recovery

Possible side effects

Possible does not mean certain: whether they appear depends on dose, duration, individual response and monitoring. Below — what to watch for and how to notice it early.

8 possible side effects

level · how often it is reported
Elevated
Black-market quality risk (fakes, contamination)
Unregulated 'research peptides' sold online; content and sterility are unverified.
How to notice: Unexpected effects, pain or infection, a stronger or weaker effect than expected.
common
Moderate
Unknown long-term safety (little human data)
Only single-dose human studies exist for GHRP-1 and alexamorelin, none for GHRP-4 and GHRP-5; long-term safety is unknown.
How to notice: Nothing to notice — the risk is what is not yet known.
common
Moderate
Abnormal tissue growth (theoretical cancer risk)
Stimulates the GH axis; a theoretical concern with active or past cancer.
How to notice: No direct signs — the point is not to fuel existing growths.
rare
Low
Injection pain, infection, oil cough
Local redness or soreness at injection sites.
How to notice: Soreness, lumps; a short coughing fit right after an injection.
common
Low
High prolactin / progestogenic effects
After a single dose alexamorelin raised prolactin, ACTH and cortisol (at the higher dose ACTH and cortisol more than hexarelin); GHRP-1 briefly raised cortisol.
How to notice: Lower libido, weaker erections, nipple sensitivity or discharge.
possible
Low
Insulin resistance / higher blood sugar
A GH-related rise in blood sugar is possible, as with other secretagogues; not studied for these peptides.
How to notice: Thirst, more hunger, energy crashes after carbs.
possible
Low
Water retention / bloating
Mild fluid retention is possible with GH stimulation; alexamorelin also raised aldosterone, a sodium-retaining hormone.
How to notice: Puffy face and ankles, softer look, quick weight jumps.
possible
Low
Numbness, tingling, carpal tunnel
GH-driven fluid retention can press on nerves (tingling, numb fingers), as with GH itself; unstudied for these peptides.
How to notice: Numb or tingling fingers, especially at night.
rare

What the levels mean

Lowbackground — just be aware
Moderatewatch for signs
Elevatedneeds regular control
Highcritical — can be life-threatening or permanent

Level: general category from the literature, not your personal risk

How often

common
reported often
possible
reported in some people
rare
reported occasionally

How to lower the risks

For 4 of 8 possible side effects there are specific ways to lower the chance: everyday measures, supplements and options a doctor may consider. For the rest — general advice. No measure removes a risk completely.

ElevatedBlack-market quality risk (fakes, contamination)

Products obtained without a prescription are often fake, mislabeled or non-sterile, and there is no way to check at home. For legal supplements, look for third-party testing (Informed Sport, NSF).

ModerateUnknown long-term safety (little human data)

What is unknown cannot be lowered, only avoided; tell your doctor what you have taken.

ModerateAbnormal tissue growth (theoretical cancer risk)

No check-up or blood test lowers this risk; avoid with any personal or family history of cancer.

Low-level side effects

Injection site
Sterile technique, never share needles, vials or pens; see a doctor for a hot, swollen site. If equipment was ever shared, test for HIV and hepatitis B/C and ask about hepatitis B vaccination.
Prolactin
Test prolactin if libido drops; a doctor decides on correction.
Measure
Regular blood tests
How each option helps (1)
  • Regular blood tests — Prolactin testing matters with 19-nor compounds and helps explain low libido or nipple discharge.
Blood sugar
More daily movement, fewer fast carbs, check fasting glucose and HbA1c.
Measure
Glucose monitoringRegular blood testsRegular cardio trainingWorking with a doctor
How each option helps (7)
  • Glucose monitoring — Rising fasting readings reveal insulin resistance from GH or other drugs early.
  • Regular blood tests — Fasting glucose, insulin and HbA1c catch rising blood sugar early — key with GH, its secretagogues and insulin.
  • Regular cardio training — Improves insulin sensitivity — useful against the blood-sugar rise from GH and its secretagogues.
  • Working with a doctor — Interprets glucose markers and treats early metabolic problems.
  • Berberine — Meta-analyses: lower fasting glucose and HbA1c (about 0.6% in type 2 diabetes); smaller effect when glucose is normal.
  • Alpha-lipoic acid — Small drops in fasting glucose, insulin and HbA1c in meta-analyses; no real counter to GH- or insulin-driven resistance.
  • Psyllium husk fiber — Slows sugar absorption: lower fasting glucose and HbA1c, mostly in people with diabetes.
Water retention
Steady salt and water intake, cardio, check estradiol.
Measure
Working with a doctor
How each option helps (1)
  • Working with a doctor — Tells harmless water retention from swelling due to heart, kidney or liver trouble; steroid labels warn that edema can come with heart failure.
Numbness
See a doctor: numbness from GH-type drugs often eases after stopping; other causes need tests — vitamin B12 on metformin, copper with long-term high-dose zinc.
Measure
Working with a doctor
How each option helps (1)
  • Working with a doctor — Finds treatable causes of numbness early: low vitamin B12 on metformin, copper deficiency from excess zinc, nerve compression from GH-driven swelling.

Check-ups and blood tests

Which tests and check-ups to do and when. This is a guide — agree the exact schedule with your doctor.

Baseline tests
your own starting values — every later result is compared with them
Fasting glucose, insulin, HbA1c
Prolactin
IGF-1
While taking
about 4–6 weeks in, then every 6–8 weeks — agree the exact schedule with your doctor
Fasting glucose, insulin, HbA1c
Prolactin
IGF-1
After stopping
4–8 weeks after stopping (later after long-acting injections), then until values return to baseline
Fasting glucose, insulin, HbA1c

Which doctors can help

Sports physiciancoordinates everything

Get medical help at once if

  • A new lump (including in the neck), trouble swallowing or persistent hoarseness, unexplained weight loss, or blood in stool or urine — see a doctor promptly.

In an emergency, call your local emergency number.

Myth & fact

Myth

“Alexamorelin is a distinct, gentler alternative to hexarelin.”

Fact

In lab tests human liver cells turned it into hexarelin itself, and in a human study it released as much GH as hexarelin but, at the higher dose, more ACTH and cortisol.

Combinations

No specific combination notes for this substance yet. The stack check still adds up side effects that several substances share.

Check combinations →

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