GHRP-6

GHRP-6 (Inj)

GHRP-6 (Growth Hormone Releasing Peptide-6) is a synthetic hexapeptide GH secretagogue that binds to the ghrelin receptor (GHS-R1a), stimulating GH release from the pituitary. It was one of the first GHRPs developed and remains widely used in research. Compared to GHRP-2, GHRP-6 produces a slightly less potent GH pulse but has a stronger appetite-stimulating effect and is noted for its anti-inflammatory and gastric motility benefits.

Dosing Protocols

— 2 mg Vial —

Reconstitute: Add 3.0 mL bacteriostatic water → ~0.67 mg/mL concentration.
Typical daily range: 300–900 mcg total (split into 3 doses with gradual titration).
Easy measuring: At 0.67 mg/mL, 1 unit = 0.01 mL ≈ 6.67 mcg on a U-100 insulin syringe.
Storage: Lyophilized: freeze at −20 °C; reconstituted: refrigerate at 2–8 °C, use within 7 days.

Schedule: Three subcutaneous injections daily for 8–12 weeks, spaced at least 4 hours apart.
Cycle Length: 8–12 weeks; rotate injection sites.
Goal: Stimulate pulsatile GH release to support muscle growth, fat loss, and recovery.

Frequency: Inject three times daily subcutaneously, spaced at least 4 hours apart (morning, midday, bedtime). Each injection should be administered on an empty stomach (2–3 hours after meals, 30 minutes before eating) to maximize GH release.

Phase	Dose	Syringe (U-100)
Weeks 1–2	100 mcg per injection (300/day)	15 units (0.15 mL)
Weeks 3–4	200 mcg per injection (600/day)	30 units (0.30 mL)
Weeks 5–12	300 mcg per injection (900/day)	45 units (0.45 mL)

— 5 mg Vial —

Reconstitute: Add 3.0 mL bacteriostatic water → ~1.67 mg/mL concentration.
Typical daily range: 300–900 mcg total (split into 3 doses with gradual titration).
Easy measuring: At 1.67 mg/mL, 1 unit = 0.01 mL ≈ 16.7 mcg on a U-100 insulin syringe.
Storage: Lyophilized: freeze at −20 °C; reconstituted: refrigerate at 2–8 °C, use within 7 days.

Schedule: Three subcutaneous injections daily for 8–12 weeks, spaced at least 4 hours apart.
Cycle Length: 8–12 weeks; rotate injection sites.
Goal: Stimulate pulsatile GH release to support muscle growth, fat loss, and recovery.

Frequency: Inject three times daily subcutaneously, spaced at least 4 hours apart (morning, midday, bedtime). Each injection should be administered on an empty stomach to maximize GH release.

Phase	Dose	Syringe (U-100)
Weeks 1–2	100 mcg per injection	6 units (0.06 mL)
Weeks 3–4	200 mcg per injection	12 units (0.12 mL)
Weeks 5–12	300 mcg per injection	18 units (0.18 mL)

— 10 mg Vial —

Reconstitute: Add 3.0 mL bacteriostatic water → ~3.33 mg/mL concentration.
Typical daily range: 300–900 mcg total (split into 3 doses with gradual titration).
Easy measuring: At 3.33 mg/mL, 1 unit = 0.01 mL ≈ 33.3 mcg on a U-100 insulin syringe.
Storage: Lyophilized: freeze at −20 °C; reconstituted: refrigerate at 2–8 °C, use within 7 days.

Schedule: Three subcutaneous injections daily for 8–12 weeks, spaced at least 4 hours apart.
Cycle Length: 8–12 weeks; rotate injection sites.
Goal: Stimulate pulsatile GH release to support muscle growth, fat loss, and recovery.

Frequency: Inject three times daily subcutaneously, spaced at least 4 hours apart (morning, midday, bedtime). Each injection should be administered on an empty stomach to maximize GH release.

Phase	Dose	Syringe (U-100)
Weeks 1–2	100 mcg per injection	3 units (0.03 mL)
Weeks 3–4	200 mcg per injection	6 units (0.06 mL)
Weeks 5–12	300 mcg per injection	9 units (0.09 mL)

Benefits

• Stimulates significant GH release from the pituitary
• Increases IGF-1 levels
• Strongly stimulates appetite — useful in cachexia and wasting research
• Promotes lean muscle mass
• Accelerates recovery from injury and exercise
• Anti-inflammatory — inhibits pro-inflammatory cytokines
• Gastric motility improvement — protective effects on GI mucosa
• Improves sleep quality
• Reduces liver damage markers in hepatic injury models
• Cardioprotective — reduces ischemia-reperfusion damage

Mechanism of Action

GHRP-6 binds to GHS-R1a (ghrelin receptor), stimulating GH release from pituitary somatotrophs both directly and by amplifying GHRH signaling. It also suppresses somatostatin tone. GHRP-6 has notable anti-inflammatory activity: it inhibits NF-κB signaling and reduces TNF-α, IL-1β, and IL-6 production in research models. It promotes gastric motility via ghrelin receptor activation in the GI tract, and has demonstrated mucosal protective effects. The appetite stimulation is stronger than GHRP-2 due to greater ghrelin-mimetic potency at peripheral receptors.

Side Effects

• Strong appetite stimulation — often the primary complaint
• Water retention
• Elevated cortisol and prolactin at higher doses
• Tingling or numbness
• Fatigue post-injection
• Hypoglycemia risk when taken fasted and not eating afterward
• Receptor desensitization with continuous use

Side Effect Management

Same general management as GHRP-2. Cycle to prevent desensitization. Manage appetite stimulation by planning meals around injections. Take on empty stomach for best GH response but have food available shortly after. Avoid combining with insulin if hypoglycemia is a concern.

Contraindications

• Active malignancy (GH/IGF-1 pathway stimulation)
• Acromegaly or pituitary adenoma
• Pregnancy and lactation
• Insulin-dependent diabetes with tight glycemic control

Research Citations

• Arvat E et al. (1997). Comparison of GHRP-2 and GHRP-6. Journal of Clinical Investigation. DOI: 10.1172/JCI119559
• Chang L et al. (2012). GHRP-6 reduces inflammation and promotes liver repair. Peptides. DOI: 10.1016/j.peptides.2012.01.006
• Granado M et al. (2002). GHRP-6 prevents liver damage. European Journal of Pharmacology. DOI: 10.1016/S0014-2999(01)01192-0

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