Tirzepatide is a 39 amino acid synthetic peptide developed from glucose-dependent insulinotropic polypeptide (GIP) to have high affinity for both GIP and glucagon-like peptide-1 (GLP-1) receptors. (3,5) As gut-derived incretin hormones, GIP and GLP-1 are endogenously released in the intestine in response to nutrient intake.(3,4,5) Tirzepatide’s dual agonist activity of GIP and GLP-1 have made it known as the first “twincretin.”(3,4) Both GIP and GLP-1 play key parts in glucose homeostasis by stimulating pancreatic beta cells to release insulin. (3,4) Whereas other peptides like semaglutide only act on GLP-1, tirzepatide’s activity on GIP additionally stimulates glucagon secretion and glucose-dependent secretion of insulin. (1,3,5). Through its dual action, studies have shown that tirzepatide enhances insulin secretion, increases insulin sensitivity, and reduces glucagon levels — all of which suggest great potential for future research. Research Studies: Tachibana T. Gastric inhibitory peptide. In: Ando H, Ukena K, Nagata S, eds. Handbook of Hormones: Comparative Endocrinology for Basic and Clinical Research. 2nd ed. Elsevier. 2021;235-238. Tachibana T. Glucagon-like peptide-1. In: Ando H, Ukena K, Nagata S, eds. Handbook of Hormones: Comparative Endocrinology for Basic and Clinical Research. 2nd ed. Elsevier; 2021:239-241. Forzano I, Varzideh F, Avvisato R, Jankausaks SS, Mone P, Santulli G. Tirzepatide: a systematic update. Int J Mol Sci. 2022;23(23):14631. doi: 10.3390/ijms232314631 Baker DE, Walley K, Levien TL. Tirzepatide. Hosp Pharm. 2023;58(3):227-243. doi: 10.1177/00185787221125724 De Block C, Bailey C, Wysham C, Hemmingway A, Allen SE, Peleshok J. Tirzepatide for the treatment of adults with type 2 diabetes: an endocrine perspective. Diabetes Obes Metab. 2023;25(1):3-17. doi: 10.1111/dom.14831 PLEASE NOTE, this is sold as a lyophilized powder and must be reconstituted using bacteriostatic water. The bacteriostatic water can be purchased on our site.  Syringes are also available in our store if you'd like to add those on to your order. ORDERS OF 3 OR MORE VIALS 10% OFF: USE CODE TIRZBULK10