Peptide Glossary

Peptide

A short chain of amino acids (typically 2-50) linked by peptide bonds. Peptides are smaller than proteins and can be synthesised for research and therapeutic use. In Australia, most injectable peptides are classified as Schedule 4 (Prescription Only) medicines.

Schedule 4 (S4)

A classification under Australia's Poisons Standard (SUSMP) for Prescription Only medicines. Schedule 4 substances require a valid prescription from an AHPRA-registered medical practitioner. Most peptides used in clinical settings fall under this schedule.

Schedule 9 (S9)

A classification under Australia's Poisons Standard for Prohibited Substances. Schedule 9 substances cannot be legally manufactured, possessed, sold, or used except for approved research. Melanotan II was reclassified to S9 in 2024.

TGA

The Therapeutic Goods Administration. Australia's regulatory body for therapeutic goods including medicines, medical devices, and biologicals. The TGA assesses and monitors products to ensure they meet acceptable standards of quality, safety, and efficacy.

AHPRA

The Australian Health Practitioner Regulation Agency. The national organisation responsible for registering and regulating health practitioners across Australia. Only AHPRA-registered medical practitioners can prescribe Schedule 4 peptides.

Compounding Pharmacy

A pharmacy licensed to prepare customised medications, including peptides, based on a prescriber's specific instructions. In Australia, compounding pharmacies must hold a TGA licence and prepare peptides to Pharmaceutical Grade standards. This is the regulated pathway for obtaining prescription peptides.

Certificate of Analysis (COA)

A document issued by a laboratory confirming the identity, purity, and potency of a substance. COAs typically include HPLC results and mass spectrometry data. In the grey market, the presence or absence of COAs is one publicly observable quality signal.

HPLC

High-Performance Liquid Chromatography. An analytical technique used to separate, identify, and quantify components in a mixture. HPLC testing is the standard method for verifying peptide purity and is referenced in Certificates of Analysis.

Reconstitution

The process of dissolving a lyophilised (freeze-dried) peptide powder using bacteriostatic water or sterile water to create an injectable solution. Reconstitution is a mathematical process involving vial size, desired concentration, and syringe units.

Bacteriostatic Water

Sterile water containing 0.9% benzyl alcohol as a preservative. Used to reconstitute lyophilised peptides. The preservative allows the reconstituted solution to be used over multiple doses, unlike sterile water which should be used in a single session.

Lyophilised

Freeze-dried. A preservation process that removes water from a substance while maintaining its molecular structure. Most peptides are supplied as lyophilised powder in sealed vials and require reconstitution before use.

Research Chemical

A label commonly used by grey market suppliers to sell peptides outside the TGA regulatory framework. Products labelled 'for research use only' or 'not for human consumption' are not subject to TGA quality controls and have no regulatory oversight on purity or potency.

ARTG

The Australian Register of Therapeutic Goods. A public database of therapeutic goods that can be legally supplied in Australia. Products on the ARTG have been evaluated by the TGA for quality, safety, and efficacy. Most compounded peptides are not individually ARTG-listed but are prepared under TGA-licensed pharmacy exemptions.

Poisons Standard (SUSMP)

The Standard for the Uniform Scheduling of Medicines and Poisons. An Australian legislative instrument that classifies substances into schedules (S2 through S9) based on their risk profile. The SUSMP determines whether a peptide requires a prescription, is available over the counter, or is prohibited.

Personal Importation Scheme

A TGA provision allowing individuals to import therapeutic goods for personal use that are not available in Australia, subject to strict conditions. The scheme has quantity limits, requires the goods to be for the importer's own use, and does not apply to Schedule 9 substances. Import enforcement was tightened in February 2026.

GLP-1 Receptor Agonist

A class of peptides that mimic the glucagon-like peptide-1 hormone, activating GLP-1 receptors to regulate blood sugar and appetite. Semaglutide and tirzepatide are the most well-known examples. In Australia, GLP-1 RAs are Schedule 4 and prescribed for type 2 diabetes and weight management.

Growth Hormone Secretagogue

A compound that stimulates the pituitary gland to release growth hormone. Includes peptides like ipamorelin, CJC-1295, and GHRP-6. These are distinct from exogenous growth hormone (hGH) and work by amplifying the body's own GH production.

Subcutaneous Injection

An injection administered into the fatty tissue layer between the skin and muscle. This is the most common delivery method for peptides. Typical injection sites include the abdomen, thigh, or upper arm. Subcutaneous injections use short, fine-gauge needles (typically 29-31 gauge).

Half-life

The time it takes for the concentration of a substance in the body to reduce by half. Peptide half-lives vary widely, from minutes (natural GH pulses) to days (semaglutide at approximately 7 days). Half-life determines dosing frequency and is a key pharmacokinetic parameter.

Bioavailability

The proportion of an administered substance that reaches systemic circulation in its active form. Subcutaneous peptide injections typically have high bioavailability. Oral peptide bioavailability is generally very low due to degradation in the GI tract, which is why most peptides are injected.

SARMs

Selective Androgen Receptor Modulators. A class of compounds that bind to androgen receptors with tissue selectivity. While not peptides, SARMs are often sold alongside peptides in grey market channels. Most SARMs are not approved for human use in Australia and are captured under Schedule 4.

Telehealth

The delivery of healthcare services remotely via digital communication tools. In Australia, telehealth consultations with AHPRA-registered practitioners can be used to obtain peptide prescriptions. Telehealth providers must comply with the same prescribing standards as in-person consultations.

Authorised Prescriber

A medical practitioner granted authority by the TGA to prescribe a specified unapproved therapeutic good to a class of patients. The Authorised Prescriber pathway is one route for legal peptide access when a product is not on the ARTG. It requires ethics committee or specialist college endorsement.

Special Access Scheme (SAS)

A TGA pathway allowing practitioners to access unapproved therapeutic goods for individual patients on a case-by-case basis. SAS Category B requires prior TGA approval. SAS Category C covers specific listed medicines that can be prescribed without prior approval. Some peptides are accessed through SAS pathways.

BPC (Body Protection Compound)

A synthetic peptide derived from a protein found in gastric juice. BPC-157 is the most studied variant, consisting of 15 amino acids. Research focuses on tissue repair, gut healing, and anti-inflammatory effects. BPC-157 is not currently scheduled in Australia's Poisons Standard.

Melanotan

A synthetic analogue of alpha-melanocyte stimulating hormone (a-MSH). Melanotan I (afamelanotide) is TGA-approved for a specific condition. Melanotan II is a broader-acting analogue reclassified to Schedule 9 (Prohibited) in Australia in 2024 due to safety concerns and widespread misuse.

NAD+

Nicotinamide adenine dinucleotide, a coenzyme found in all living cells. NAD+ is involved in cellular energy metabolism and DNA repair. While not a peptide, NAD+ infusions and precursors (NMN, NR) are commonly offered alongside peptide therapies by Australian clinics.

Pharmaceutical Grade

A quality standard indicating a substance meets the purity, potency, and safety requirements set by a recognised pharmacopoeia (such as the British Pharmacopoeia or USP). Peptides prepared by TGA-licensed compounding pharmacies are held to pharmaceutical grade standards, unlike grey market products.

ABF (Australian Border Force)

The Australian government agency responsible for border enforcement, including the detection and seizure of undeclared or prohibited therapeutic goods. ABF works with the TGA to intercept illegally imported peptides, particularly Schedule 4 and Schedule 9 substances.

Off-label Prescribing

The practice of prescribing a medicine for a purpose, age group, or dosage other than what is specified in its approved product information. In Australia, off-label prescribing is legal when a registered practitioner determines it is clinically appropriate. Many peptide prescriptions in clinical practice are off-label.