Educational content only — this is not medical advice. Nothing here is a recommendation to buy, obtain, or use Tirzepatide. Talk to a licensed clinician before making health decisions.
What it is
Tirzepatide is a synthetic 39-amino-acid peptide engineered as a dual agonist of the glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors. It has a C20 fatty-diacid side chain for albumin binding, enabling once-weekly dosing. By co-activating both incretin receptors, it enhances insulin secretion in a glucose-dependent manner, suppresses glucagon, delays gastric emptying, and reduces food intake.
What the evidence shows
The SURMOUNT-1 trial (NEJM 2022; 2,539 adults with obesity, 72 weeks) reported mean weight reductions of 15.0% (5 mg), 19.5% (10 mg), and 20.9% (15 mg) versus 3.1% with placebo. SURMOUNT-3 and -4 showed even larger effects when tirzepatide followed an intensive lifestyle lead-in or was continued after initial loss. In type 2 diabetes, SURPASS trials demonstrated HbA1c reductions of up to 2.4 percentage points, with superior glycemic control versus semaglutide 1 mg in SURPASS-2.
Risks & unknowns
Gastrointestinal side effects (nausea, diarrhea, vomiting, constipation) are the most common and are dose-dependent. Gallbladder disease, pancreatitis, hypoglycemia when combined with insulin or sulfonylureas, injection-site reactions, and modest increases in heart rate have been observed. As with other incretin agonists, medullary thyroid carcinoma and MEN2 are contraindications. Long-term cardiovascular outcomes data are being collected in ongoing trials.
Legal / regulatory status
Tirzepatide is FDA-approved as Mounjaro for type 2 diabetes and as Zepbound for chronic weight management. It is prescription-only. Compounded tirzepatide is not FDA-approved and product quality is uncertain.