Glossary
One-paragraph definitions. Every term here is also defined in place across the site — hover or tap a to see it.
Agonist
A substance that binds a receptor and activates it, producing the effect the body’s own signal would. Semaglutide is a GLP-1 receptor agonist.
Angiogenesis
The growth of new blood vessels from existing ones. Central to wound healing — and a reason for caution with compounds that promote it, since tumours also need new vessels.
Bacteriostatic water
Sterile water with 0.9% benzyl alcohol, which stops bacteria growing so a vial can be used over several weeks. The usual diluent for reconstitution.
Baseline
Measurements taken before a protocol starts, so later values have something to be compared against. Ideally two to four weeks of the same metric, taken the same way.
Certificate of Analysis (CoA)
A lab report on a specific batch: purity, identity and contaminants. Tells you about that batch only, and only if the lab is genuine.
Diluent
The liquid used to dissolve a lyophilised powder — usually bacteriostatic water, sometimes sterile water where a profile says so.
Endotoxin
Fragments of bacterial cell walls that can cause fever and inflammation. Measured in EU/mg on a CoA.
GHS-R1a
The ghrelin receptor. GH secretagogues like ipamorelin act here to trigger growth-hormone release.
Half-life
The time it takes for the amount of a substance in the blood to fall by half. Sets how often a compound is dosed in studies.
In vitro
Studied in cells or tissue in a dish, not in a living animal. Grade D evidence.
Intramuscular (IM)
Injected into a muscle. Absorbed faster than subcutaneous for many compounds; used in some studies, less often in community reports.
Lyophilised
Freeze-dried. Most research peptides are supplied as a lyophilised powder because it is far more stable than a solution.
RCT
Randomised controlled trial: participants are randomly assigned to the treatment or a control. The strongest single study design. Grade A.
Reconstitution
Dissolving a lyophilised powder in a diluent to make a solution of known concentration.
Secretagogue
A substance that causes another substance to be secreted. GH secretagogues make the pituitary release growth hormone.
Subcutaneous (SC)
Injected into the fat layer just under the skin, as opposed to into muscle (IM) or a vein (IV).
U-100
The standard insulin syringe scale: 100 units per millilitre, so 10 units = 0.1 ml.
Washout
A planned period with no compound, long enough (usually several half-lives) for levels to return to baseline before the next phase or comparison.