Hexarelin

PMID: 9156035, DOI: 10.1046/j.1365-2265.1997.1240940.x

Population: Healthy male adults

Dose protocol: IV bolus 0.5-2.0 µg/kg

Key findings: Acute GH rise was dose-responsive with early peak and return toward baseline over hours.

Notes: Strongest support for acute biomarker-level pharmacodynamics.

PMID: 8954038, DOI: 10.1210/jcem.81.12.8954038

Population: Healthy adult men

Dose protocol: IV 0.0-1.0 µg/kg. Plus GHRH 1.0 µg/kg with or without 0.125 µg/kg.

Key findings: Dose-response behavior for GH/PRL/cortisol with plateau-like GH response near 1.0 µg/kg and notable coadministration interactions.

Notes: Useful for axis signal interpretation, not long-horizon efficacy.

PMID: 9437229, DOI: 10.1530/eje.0.1370635

Population: Prepubertal children, pubertal children, adults, elderly adults

Dose protocol: IV up to 2.0 µg/kg

Key findings: GH, PRL, ACTH, and cortisol responses varied with age.

Notes: Supports phenotype-stratified interpretation.

PMID: 10404825, DOI: 10.1210/jcem.84.7.5811

Population: Healthy young male volunteers

Dose protocol: IV hexarelin with CRH/desmopressin interaction paradigms

Key findings: Demonstrated GH secretagogue effects on pituitary-adrenal activation with hypothalamic AVP/CRH pathway involvement.

Notes: Mechanistic insight for safety/performance interpretation.

PMID: 10341859, DOI: 10.1046/j.1365-2265.1999.00609.x

Population: Healthy adults

Dose protocol: Acute and repeated exposure paradigms

Key findings: Confirmed recurrent ACTH/cortisol/PRL stimulation concerns during exposure with caution around prolonged use.

Notes: Supports concern for repeated endocrine perturbation in longer exposure.

PMID: 8719303, DOI: 10.1007/BF03349794

Population: Healthy adults

Dose protocol: 1 µg/kg IV sequential stimulation over 120-minute spacing

Key findings: Second GH responses declined in repeat paradigms, with less attenuation than repeated GHRH alone.

Notes: Supports adaptive response/attenuation concerns in repeated dosing.

PMID: 8977750, DOI: 10.1046/j.1365-2265.1996.00841.x

Population: Adult volunteers

Dose protocol: GHRH 1.0 µg/kg IV, hexarelin 1.0 µg/kg IV with 120-min separation

Key findings: Sequential protocol improved characterization of GH reserve with low false-negative behavior.

Notes: Diagnostic, not therapeutic outcome oriented.

Laron Z et al. 1995. "Intranasal administration of the GHRP hexarelin accelerates growth in short children." Clin Endocrinol (Oxf). 43(5):631-635. PMID: 8548949. DOI: 10.1111/j.1365-2265.1995.tb02929.x.

Population: Prepubertal short children

Dose protocol: Intranasal 60 µg/kg three times/day, up to 8 months

Key findings: IGF-I increased and growth velocity improved in this pediatric protocol.

Notes: Not directly transferable to healthy-adult enhancement use.

Loche S et al. 1997. "The growth hormone response to hexarelin in children: reproducibility and effect of sex steroids." J Clin Endocrinol Metab. 82(3):861-864. PMID: 9062497. DOI: 10.1210/jcem.82.3.3795.

Population: Short normal children

Dose protocol: IV hexarelin 2.0 µg/kg

Key findings: Reproducible GH responses with increased sensitivity after sex-steroid priming.

Notes: Supports pediatric phenotype/context dependence rather than broad adult claims.

Frieboes RM et al. 2004. "Hexarelin decreases slow-wave sleep and stimulates the secretion of GH, ACTH, cortisol and prolactin during sleep in healthy volunteers." Psychoneuroendocrinology. 29(7):851-860. PMID: 15177700. DOI: 10.1016/S0306-4530(03)00152-5.

Population: Healthy young volunteers

Dose protocol: 4 × 50 µg across one night

Key findings: Lower stage-4/slow-wave measures with concurrent endocrine increases.

Notes: Small sample. No long-horizon performance findings.

Benso A et al. 2002. "Impact of two or three daily subcutaneous injections of hexarelin, a synthetic growth hormone (GH) secretagogue, on 24-h GH, prolactin, adrenocorticotropin and cortisol secretion in humans." Eur J Endocrinol. 146(3):310-316. PMID: 11888836. DOI: 10.1530/eje.0.1460310.

Population: Healthy volunteers

Dose protocol: SC hexarelin 1.5 µg/kg, 2-3 injections/day, 24-h monitoring

Key findings: 24-h GH secretion increased. Endocrine profiles changed with repeated administration and showed response adaptation.

Notes: Supports repeated-dose signal-shape behavior more than clinical outcome efficacy.

WADA Prohibited List, S2.2.4 GH secretagogues and GH-releasing peptides; https: //www.wada-ama.org/what-is-prohibited

Population: Competitive athlete governance framework

Dose protocol: N/A

Key findings: GH-releasing factors/secretagogues are prohibited-class compounds under WADA S2.

Notes: Governance reference only. Not a clinical efficacy source.