# Med Tirzepatide — A herbarium of the tirzepatide evidence base > An editorial materia-medica record of tirzepatide: dual GIP/GLP-1 receptor agonism, the SURPASS and SURMOUNT programs, half-life, and labeled dose ranges. Not medical advice. Synthetic incretin agonist, dual GIP/GLP-1, hybrid backbone, fatty-acid tail — the literature pressed, cataloged, and indexed for the careful reader. ## The specimen, in plain terms Tirzepatide is a once-weekly injectable medicine approved by the U.S. FDA for type 2 diabetes (2022), obesity (2023), and obstructive sleep apnea. It works by activating two gut-hormone signals at once — GIP and GLP-1 — the signals your body naturally releases after eating to prompt insulin release and curb appetite. By engaging both signals with a single molecule, it consistently outperformed older drugs in large trials. In the flagship obesity trial (SURMOUNT-1, 2,539 people), participants at the highest dose lost an average of 20.9% of their body weight over 72 weeks [8]. In a head-to-head comparison against semaglutide in people without diabetes (SURMOUNT-5), tirzepatide produced 20.2% weight loss versus 13.7% [11]. The most commonly reported side effects are nausea, constipation, and diarrhea — mostly during dose escalation. What people report, including the downsides, is filed on [the effects page](/effects). This site is an editorial catalog of the evidence — not a clinic, not a vendor. ## The compound, in one paragraph Tirzepatide — clinical designation LY3298176 — is a 39-amino-acid synthetic peptide engineered around the native glucose-dependent insulinotropic polypeptide (GIP) sequence, with a C20 fatty di-acid moiety appended to the backbone so that the finished molecule binds plasma albumin at roughly 99 percent and persists in circulation with an elimination half-life near five days [1]. That single structural decision — a fatty tail in service of albumin tethering — is what converts a peptide into a once-weekly subcutaneous therapeutic. The molecule activates two receptors at once: the GIP receptor and the glucagon-like peptide-1 (GLP-1) receptor, with notably imbalanced affinities and a biased signaling profile at GLP-1R that favors cAMP over beta-arrestin recruitment [2]. The phenotype produced in humans is now extensively cataloged: glucose lowering in type 2 diabetes, weight reduction in obesity, and a widening file of indication-adjacent effects in sleep apnea, hepatic steatohepatitis, and heart failure with preserved ejection fraction. ## What this site is — and what it is not Med Tirzepatide is an independent editorial project. It catalogs the published evidence base on tirzepatide the way a Victorian pharmacopeia catalogued its materia medica: one specimen per plate, one trial per page, each entry filed with the citation that supports it. It is not a clinic. It does not employ clinicians, does not provide medical advice, and does not manufacture, sell, or distribute any product. The compound itself is an FDA-approved prescription medicine in the United States — approved for adults with type 2 diabetes in 2022 and for chronic weight management in adults with obesity or overweight with weight-related comorbidities in 2023 [18]. The brand names under which the approved formulation is dispensed are not used on this site. The site refers to the compound by its International Nonproprietary Name only. ## How the evidence is organized here The literature is filed into six chapters. Mechanism is treated first: the dual incretin biology, the structural basis for biased agonism, and the pharmacokinetic profile that supports weekly dosing. The clinical record follows, organized by program. SURPASS (1 through 5, plus the cardiovascular outcomes trial SURPASS-CVOT) carries the type 2 diabetes file. SURMOUNT (1 through 5, plus SURMOUNT-OSA) carries the weight-management and obstructive sleep apnea files. SYNERGY-NASH carries the metabolic dysfunction-associated steatohepatitis (MASH) file. SUMMIT carries the heart failure with preserved ejection fraction file. A dosage page reports the trial-protocol titration scheme and the FDA-labeled maintenance doses. A references page closes the volume with full citations and digital object identifiers. The questions page collects the practical confusions a careful reader runs into in the early literature. ## Headline outcomes, briefly In SURMOUNT-1, mean weight reduction at 72 weeks reached 15.0, 19.5, and 20.9 percent at the 5, 10, and 15 mg weekly doses, against 3.1 percent on placebo in adults with obesity or overweight without diabetes [8]. In SURPASS-2, against semaglutide 1 mg at 40 weeks in type 2 diabetes, the three tirzepatide doses produced HbA1c reductions of −2.01, −2.24, and −2.30 percentage points versus −1.86 for semaglutide, with body-weight reductions of −7.6 to −11.2 kilograms versus −5.7 [6]. In SURMOUNT-5, the first head-to-head obesity trial against semaglutide, tirzepatide produced a mean weight reduction of 20.2 percent against 13.7 percent at 72 weeks [11]. In SURPASS-CVOT, the first head-to-head cardiovascular outcomes trial between two incretin therapies, tirzepatide met non-inferiority against dulaglutide for the three-component major adverse cardiovascular events endpoint and was associated with a 16 percent lower all-cause mortality hazard (HR 0.84) over a median four-year follow-up [15]. These numbers are reproduced in their original context on the research page, with the trial designs and uncertainties intact. ## Editorial standards Every quantitative claim on this site is sourced to a primary publication, an FDA label, or a peer-reviewed review of the program. Brand names for the approved formulation are not used. Doses are reported as they appeared in the trial protocols or on the FDA label — never as a recommendation, never in second person. Adverse events, contraindications, and unresolved questions are reported alongside the efficacy numbers; the page on caveats is not an afterthought. The herbarium frame is editorial license: it does not soften the science, and it does not embellish it. --- An independent pharmacopoeial digest of the published tirzepatide record — not a clinic, not a dispensary, not medical guidance.