GLP-1 Agonist Peptides

Activates GLP-1 receptors

Mechanism

GLP-1 (glucagon-like peptide-1) receptor agonists are a class of peptides that mimic the incretin hormone GLP-1, which your gut naturally releases after eating. They have become the most impactful class of peptides in modern medicine, with FDA-approved drugs generating over $50 billion in annual revenue. Semaglutide (Ozempic/Wegovy), tirzepatide (Mounjaro/Zepbound), and liraglutide (Victoza/Saxenda) are the major approved compounds. Retatrutide (a triple agonist targeting GLP-1, GIP, and glucagon receptors) is in late-stage clinical trials.

These peptides simultaneously address weight loss, blood sugar control, cardiovascular risk, and potentially liver disease and kidney disease. Clinical trials have shown cardiovascular mortality reduction, fatty liver improvement, and even potential benefits for Alzheimer's disease and addiction. Their broad metabolic effects make them relevant far beyond their original indication of type 2 diabetes.

This page collects every GLP-1 receptor agonist on PeptideWiki. Browse individual profiles for specific mechanisms, dosing, and clinical trial data.

Peptides (3)

Semaglutide

Metabolic & Weight Loss

Semaglutide is a medication that mimics a natural fullness hormone (GLP-1) in the body. It is FDA-approved as Wegovy for weight management and Ozempic for type 2 diabetes, with significant effects on appetite control and blood sugar regulation.

Tirzepatide

Metabolic & Weight Loss

Tirzepatide is a dual-action medication that activates both GIP and GLP-1 receptors, two key fullness and blood sugar hormones. It is FDA-approved as Mounjaro for type 2 diabetes and Zepbound for weight management, outperforming semaglutide in head-to-head trials.

Liraglutide

Metabolic & Weight Loss

Liraglutide is a medication that mimics a natural fullness hormone (GLP-1) in the body. It is FDA-approved as Victoza for type 2 diabetes and Saxenda for weight management, with an extensive record of clinical safety and effectiveness data.

Frequently Asked Questions

GLP-1 agonists work on multiple systems simultaneously: they reduce appetite centrally (in the brain's hypothalamus), slow gastric emptying (so you feel full longer), improve insulin sensitivity (so your body handles nutrients more efficiently), and may directly affect fat tissue metabolism. This multi-target approach produces weight loss of 15-22% of body weight in clinical trials, which is far more than any single-mechanism drug has achieved. The dual and triple agonists (tirzepatide, retatrutide) that target additional receptors produce even greater effects.

Semaglutide activates only the GLP-1 receptor. Tirzepatide activates both GLP-1 and GIP receptors (dual agonist), which provides additional insulin secretion support and potentially greater weight loss. Retatrutide activates GLP-1, GIP, and glucagon receptors (triple agonist), adding glucagon's effects on liver fat metabolism and energy expenditure. In clinical trials, weight loss increased with each additional receptor target: semaglutide ~15-17%, tirzepatide ~20-22%, retatrutide ~24% at the highest dose in phase 2.

Compounded semaglutide and tirzepatide are produced by compounding pharmacies rather than the original manufacturers (Novo Nordisk and Eli Lilly). They contain the same active molecule but may differ in formulation, purity testing standards, and potency consistency. The FDA allows compounding when branded drugs are in shortage. Quality varies significantly between compounding pharmacies. Using a pharmacy that provides third-party purity testing and is accredited by PCAB (Pharmacy Compounding Accreditation Board) reduces but does not eliminate risk.

Gastrointestinal side effects are most common: nausea (especially during dose escalation), constipation, diarrhea, and decreased appetite. These typically improve over weeks as the body adapts. More serious but rare risks include pancreatitis, gallbladder disease, and potential thyroid concerns (a boxed warning exists for medullary thyroid carcinoma based on animal studies, though human risk appears very low). Muscle loss during rapid weight loss is a concern addressed by adequate protein intake and resistance training. Most side effects are managed by slow dose titration.

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