One class, three different approaches

Semaglutide, Tirzepatide and Retatrutide belong to the same family of incretin peptides, but they differ in how many receptors they activate at once. It is precisely this number of target receptors that is the main difference determining how they behave in metabolic research.

  • Semaglutide — single agonist (GLP-1)
  • Tirzepatide — dual agonist (GLP-1 + GIP)
  • Retatrutide — triple agonist (GLP-1 + GIP + glucagon)

What each receptor does

GLP-1 (glucagon-like peptide-1) is the best-studied target — it plays a role in glycemic regulation and satiety signaling. GIP (glucose-dependent insulinotropic polypeptide) acts complementarily and, combined with GLP-1, appears synergistic in research. The glucagon receptor adds a third axis linked to energy expenditure. Adding each further receptor broadens the range of metabolic effects under observation.

Direct comparison

SemaglutideTirzepatideRetatrutide
ReceptorsGLP-1GLP-1 + GIPGLP-1 + GIP + glucagon
TypeMono agonistDual agonistTriple agonist
Our pen5 mg10 mg10 mg
Research stageLongest studiedNewer, well documentedNewest of the three

How to choose for research

Semaglutide — the reference point

With the longest history of study, Semaglutide is a frequent choice as a reference standard against which newer molecules are compared. A simple mechanism means clearer interpretation of data.

Tirzepatide — dual mechanism

Tirzepatide is suitable when research targets the interplay of GLP-1 and GIP. Dual action is associated in the literature with more pronounced metabolic effects than monotherapy.

Retatrutide — the widest scope

Retatrutide adds the glucagon axis and is intended for research that aims to cover the broadest range of metabolic pathways at once. As the newest molecule, it is of interest for exploratory studies.

This article describes mechanisms of action solely for research and educational purposes. It is not medical advice, and the products are not intended for human consumption or for treating any disease.

Shared characteristics

We supply all three pens with HPLC-verified purity of ≥ 99%, a certificate of analysis for every batch, and in thermo-insulated packaging with a cooling pack. Regardless of the molecule you choose, proper storage after receipt is key. If you're still deciding on the format, read what a peptide pen is and how it differs from powder.