Human Growth Hormone (HGH) in Australia: Research Guide

Human growth hormone (HGH), also called somatotropin, is a 191-amino acid single-chain polypeptide synthesised and secreted by somatotroph cells in the anterior pituitary gland. It is the primary regulator of somatic growth during development, and a key regulator of metabolic processes (including protein synthesis, lipolysis, and glucose homeostasis) throughout life.

GH is secreted in pulses, with the largest pulse occurring during slow-wave sleep. Secretion is regulated by the hypothalamic-pituitary axis: growth hormone-releasing hormone (GHRH) stimulates GH release, while somatostatin inhibits it. Ghrelin (via GHS-R1a) provides an additional stimulatory input. Many GH secretagogue research compounds, including CJC-1295 and Ipamorelin, target this axis.

GH exerts its biological effects through two primary mechanisms:

• Direct GH receptor signalling, GH binds GH receptors (GHR) on target cells and activates JAK2-STAT5b signalling. Direct effects include lipolysis in adipose tissue (fat breakdown), insulin antagonism (GH is a counter-regulatory hormone), and direct anabolic effects in muscle and connective tissue
• IGF-1-mediated effects, GH stimulates hepatic production of IGF-1 (insulin-like growth factor-1), which mediates most of GH's growth-promoting effects. IGF-1 acts through IGF-1R to stimulate cell proliferation, protein synthesis, and tissue growth throughout the body

The GH/IGF-1 axis declines with age, a phenomenon called somatopause. Mean GH secretion decreases approximately 14% per decade after early adulthood, with corresponding declines in IGF-1. This decline is associated with changes in body composition (increased visceral fat, reduced lean mass), and is a subject of ongoing research into ageing and body composition.

HGH is studied across several research domains:

• Body composition, GH increases lipolysis and lean mass; studied in models of sarcopenia, GH deficiency, and metabolic syndrome
• GH deficiency models, both adult and childhood GH deficiency represent established research models for somatotropin replacement
• Metabolic effects, GH has complex effects on insulin sensitivity (short-term increases, long-term reduction), glucose metabolism, and lipid profiles; studied in insulin resistance and type 2 diabetes models
• Bone density, GH/IGF-1 axis activity correlates with bone mineral density; research into osteoporosis prevention and treatment
• Wound healing, GH has direct and IGF-1-mediated effects on tissue repair; studied in combination with peptide bioregulators
• Cardiovascular, GH-deficient adults have increased cardiovascular risk markers; GH replacement research shows improvement in lipid profiles and cardiac function markers

HGH is measured in International Units (IU) rather than by weight. The approximate conversion is 1mg ≈ 3 IU, though this can vary by formulation. For research purposes, vial selection depends on protocol duration and concentration requirements.

OzPeps stocks multiple HGH vial configurations to suit different research protocols:

• HGH 10IU × 10 vials (100IU total), suitable for shorter protocols or initial research
• HGH 24IU × 10 vials (240IU total), mid-range option for extended protocols
• HGH 40IU × 10 vials (400IU total), high-yield option for longer-duration research
• HGH 40IU Single Vial, single-vial format for protocol testing

All OzPeps HGH is sourced from suppliers with verified Certificate of Analysis (COA) and supplied as lyophilised powder for reconstitution.

HGH lyophilised powder requires reconstitution with bacteriostatic water before use. Key research reconstitution notes:

• Use bacteriostatic water (0.9% benzyl alcohol), not sterile water, to extend post-reconstitution stability
• Inject bacteriostatic water slowly down the side of the vial; do not shake, gently swirl until dissolved
• Store reconstituted HGH at 2–8°C; lyophilised powder can be stored at room temperature before reconstitution
• Use the OzPeps reconstitution calculator to determine the water volume needed for your target concentration

For a detailed peptide reconstitution guide, see: Bacteriostatic Water & Peptide Reconstitution →

An alternative approach to studying GH axis activity involves GH secretagogues, compounds that stimulate endogenous GH release rather than providing exogenous GH directly. OzPeps stocks several secretagogues that are used in GH axis research:

• CJC-1295 + Ipamorelin blend, GHRH analogue + GHS-R1a agonist; stimulates pulsatile GH release
• CJC-1295, standalone GHRH analogue
• Ipamorelin, selective GHS-R1a agonist with low cortisol/prolactin side-effect profile in preclinical models
• Tesamorelin, stabilised GHRH analogue with strong clinical evidence base (approved for HIV-associated lipodystrophy)

See: CJC-1295 + Ipamorelin Research Guide →

Human growth hormone is a Schedule 4 prescription-only medicine in Australia under the TGA's Therapeutic Goods (Standard for Medicinal Products) Order. Clinical prescription is restricted to specific approved indications including GH deficiency diagnosis and treatment.

OzPeps supplies HGH strictly for in-vitro laboratory and scientific research use only, not for human or animal administration. All products are sourced from suppliers with verified supplier COA. Researchers must ensure compliance with applicable regulations in their jurisdiction. See: Australian research peptide legality guide →