GHRP-6 Dosage, half-life & reference guide
Also known as Growth Hormone Releasing Peptide-6
One of the first growth hormone releasing peptides, with one standout effect: strong appetite stimulation.
- Studied range
- 100–300 mcg
- How often
- 2–3× daily
- Half-life
- ~20 min
- Evidence
- ●●
●Moderate - Route
- SubQ injection
Studied in research — not a recommendation.
How it works.
First-generation GH secretagogue that stimulates GH via ghrelin receptor activation. Significantly increases appetite (shown in animals and widely reported by users) — useful for those seeking to bulk. Also raises cortisol and prolactin moderately.
Commonly reported: Intense hunger soon after a dose, water retention and puffiness, and a head rush or flush after injecting. Useful for people who want to eat more, but the hunger can be overwhelming for those trying to stay lean. Also raises cortisol and prolactin.
Where GHRP-6 works.
Brain, nerves & sleep
Reported by users. GH is rising too, and sleep often deepens.
Appetite & metabolism
In animals. Significantly increases appetite (shown in animals and widely reported by users) — useful for those seeking to bulk.
Muscle
Reported by users. If you can channel the appetite into quality nutrition, GHRP-6 is a useful tool for hard-gainers.
An area lights for what a peptide is used for and what people report, with the evidence beside it. It isn’t a promise that it works there.
Week by week.
What to expect in the first 8 weeks
Day 1–7Community
The hunger is real — plan for it
GHRP-6's signature effect hits fast. Commonly reported: intense hunger within about 15–20 minutes of a dose. If you're trying to bulk, this is a feature; if you're trying to stay lean, plan your meals around it. GH is rising too, and sleep often deepens.
The science
GHRP-6 is a first-generation ghrelin receptor agonist. In rats its appetite effect runs through hypothalamic NPY neurons (Dickson & Luckman 1997). The hunger signal is pharmacological, not psychological — it activates the same receptors as the "hunger hormone" ghrelin.
Sources- Dickson & Luckman (1997)
- Bowers et al. (1984)
Updated Sep 2026
Day 7–56Community
GH is elevated — use the appetite wisely
If you can channel the appetite into quality nutrition, GHRP-6 is a useful tool for hard-gainers. Commonly reported: strong hunger plus water retention or puffiness. GH output is strong, IGF-1 is climbing, and the extra calories feed growth and repair.
The science
GHRP-6 produces robust GH release, with prolactin and cortisol roughly doubling after a dose (Bowers 1990). Users commonly hold that it desensitizes faster than GHRP-2 and rotate between the two, though no study compares them. Whether the appetite effect lasts hasn't been studied for GHRP-6; with related agonists it faded over weeks to months (Mericq 2003; Nass 2008).
Sources- Bowers et al. (1990)
Updated Sep 2026
Any dayClinical
What GHRP-6 is built on
GHRP-6 (1984) was the first growth hormone releasing peptide with strong activity in living animals, and it opened the secretagogue field. Human data are small, single-dose studies, and cleaner options like Ipamorelin have largely replaced it. Still has a niche for hardgainers who want the appetite boost as a primary feature.
The science
GHRP-6 was one of the first synthetic GH secretagogues developed. It helped identify the ghrelin receptor (GHS-R1a) and establish the GHRH+GHRP synergy paradigm (Bowers 1990). Less selective than newer peptides — raises cortisol, prolactin, and appetite in addition to GH. Never approved; FDA lists it in compounding category 2, citing its effects on cortisol and blood glucose.
Sources- Bowers et al. (1984)
- Bowers et al. (1990)
Updated Sep 2026
Day 1 is the day you start it.
Mixing and a typical run.
Example numbers
Reconstitution example
Reconstitute a 5 mg vial of GHRP-6 with 2 mL of bacteriostatic water and a 200 mcg dose is 8 units on a U-100 syringe, about 25 doses per vial.
- Vial
- 5 mg
- Water
- 2 mL
- Amount
- 200 mcg
Draw to8 units
0.3 mL insulin syringe · 30 units
Run notes
- Cycle
- 8–12 weeks. Strong appetite effect means some cycle more conservatively.Community practice — opinions vary. Not a clinical recommendation.
- Timing
- Fasted injection essential — food blunts GH pulse significantly.
- Route
- SubQ injection
- Stacks
- CJC-1295 no DAC, Sermorelin
Safety.
Common side effects
- Strong appetite increase
- Water retention
- Fatigue
- Cortisol elevation
- Prolactin elevation
Goes with.
Questions people ask.
What is GHRP-6?
One of the first growth hormone releasing peptides, with one standout effect: strong appetite stimulation.
How is GHRP-6 dosed in research?
The research range for GHRP-6 is 100–300 mcg, 2–3x daily. Studied in research — not a recommendation.
How long does GHRP-6 last?
The half-life of GHRP-6 is ~20 min.
What do people report on GHRP-6?
Commonly reported on GHRP-6: intense hunger soon after a dose, water retention and puffiness, and a head rush or flush after injecting. Useful for people who want to eat more, but the hunger can be overwhelming for those trying to stay lean. Also raises cortisol and prolactin.
Is GHRP-6 safe?
The research basis for GHRP-6 is moderate: animal studies + some human data. Common side effects in the library: strong appetite increase, water retention, fatigue, cortisol elevation and prolactin elevation.
What does GHRP-6 stack with?
Common stacks for GHRP-6: CJC-1295 no DAC and Sermorelin.
Research.
Reference.
- Cadence
2–3× daily
2–3x daily
- Half-life
~20 min
- Research basis
●●
●ModerateAnimal studies + some human data
PepVault for iPhone
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