GLP-1 peptides
GLP-1 peptides are a group of compounds that share a common mechanism. This page lists every GLP-1 peptide in the CalculatePeptide database with links to individual dosage and reconstitution calculators.
GLP-1 peptides in this calculator
GLP-1 dosage comparison
Side-by-side factual comparison of common vial sizes, reported half-life, and mechanism. No dose recommendations.
| Peptide | Common vial sizes | Reported half-life | Mechanism |
|---|---|---|---|
| Semaglutide | 2, 3, 5, 10 mg | ~7 days | A GLP-1 receptor agonist that mimics the GLP-1 incretin hormone and binds to GLP-1 receptors in pancreatic and neural tissue. |
| Tirzepatide | 5, 10, 15, 30, 60 mg | ~5 days | A dual GLP-1 and GIP receptor agonist that simultaneously activates two incretin receptors through a single engineered peptide. |
| Retatrutide | 5, 10, 20 mg | ~6 days | A triple agonist of the GLP-1, GIP, and glucagon receptors, investigated in clinical trials as a multi-receptor incretin analog. |
GLP-1, dual agonists, and triple agonists
The GLP-1 class started with single-receptor agonists like semaglutide, which activate the GLP-1 receptor only. More recent compounds activate multiple incretin receptors simultaneously. Tirzepatide is a dual agonist that activates both the GLP-1 receptor and the glucose-dependent insulinotropic polypeptide (GIP) receptor. Retatrutide is a triple agonist that activates GLP-1, GIP, and the glucagon receptor; some online discussions informally refer to triple agonists as "GLP-3," though this is not standard scientific nomenclature.
From a reconstitution-math standpoint, all three are handled identically by the calculator — the peptide mass, water volume, target dose, and syringe type are the only inputs that matter. The number of receptors a peptide activates is pharmacologically significant but does not change how you compute a draw.