# A Critical Analysis of the Clinical Use of Incretin-Based Therapies: Efficacy and Adverse Events

**Authors:** Ilana Radparvar, Devendra K. Agrawal

PMC · DOI: 10.26502/acmcr.96550740 · 2026-03-13

## TL;DR

Incretin-based therapies like GLP-1 and GIP agonists show promise for treating obesity and diabetes but come with side effects and limited long-term safety data.

## Contribution

This paper critically analyzes the clinical efficacy and safety profile of incretin-based therapies, highlighting their expanding roles and limitations.

## Key findings

- GLP-1 and GIP agonists like semaglutide and tirzepatide significantly reduce weight and improve glycemic control.
- Tirzepatide outperforms semaglutide in weight loss due to dual-receptor activation.
- Adverse effects include gastrointestinal issues and potential risks for gallbladder disease or pancreatitis.

## Abstract

Obesity is a major public health challenge in the United States, despite widespread implementation of regulated diet plans, exercise programs, behavioral interventions, and surgical procedures. The emergence of incretin-based therapies, particularly GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide) receptor agonists, has transformed the therapeutic landscape for initially type 2 diabetes and now obesity. Beyond their metabolic effects, incretin therapies exert meaningful cardiovascular, gastrointestinal, and neuroprotective actions. Semaglutide, a GLP-1 receptor agonist, and tripeptide, a dual GLP-1/GIP agonist, demonstrate substantial weight reduction, improved glycemic control, and reductions in cardiometabolic risk factors. Tirzepatide consistently produces greater weight loss effects than semaglutide, likely due to synergistic dual-receptor effects. However, these therapies are accompanied by adverse effects, most commonly gastrointestinal disturbances, and, less frequently, gallbladder disease, pancreatitis, or rare ophthalmologic concerns. Long-term safety data remain limited, particularly in older adults, pediatric patients, pregnant women, and individuals with comorbid disease. Emerging evidence also suggests potential roles in cancer prevention, hypertension, and neurodegenerative disease. As the indications for incretin-based therapies continue to expand, longer-duration trials and more diverse study populations will be essential to fully examine their long-term clinical effects. Though these agents hold considerable promise, careful and informed use remain vital.

## Linked entities

- **Proteins:** GCG (glucagon), GIP (gastric inhibitory polypeptide)
- **Diseases:** obesity (MONDO:0011122), type 2 diabetes (MONDO:0005148), pancreatitis (MONDO:0004982), gallbladder disease (MONDO:0005281)

## Full-text entities

- **Genes:** GCG (glucagon) [NCBI Gene 2641] {aka GLP-1, GLP1, GLP2, GRPP}, Gcg (glucagon) [NCBI Gene 24952] {aka GLP-1, Glp1, Glp2}, PYY (peptide YY) [NCBI Gene 5697] {aka PYY-I, PYY1}, GIP (gastric inhibitory polypeptide) [NCBI Gene 2695], INS (insulin) [NCBI Gene 3630] {aka IDDM, IDDM1, IDDM2, ILPR, IRDN, MODY10}, Glp1r (glucagon-like peptide 1 receptor) [NCBI Gene 25051] {aka Glip, RATGL1RCP}, APP (amyloid beta precursor protein) [NCBI Gene 351] {aka AAA, ABETA, ABPP, AD1, APPI, CTFgamma}, CALCA (calcitonin related polypeptide alpha) [NCBI Gene 796] {aka CALC1, CGRP, CGRP-I, CGRP-alpha, CGRP1, CT}, GLP1R (glucagon like peptide 1 receptor) [NCBI Gene 2740] {aka GLP-1, GLP-1-R, GLP-1R}, SLC9A3 (solute carrier family 9 member A3) [NCBI Gene 6550] {aka DIAR8, NHE-3, NHE3}, LEP (leptin) [NCBI Gene 3952] {aka LEPD, OB, OBS}, CRP (C-reactive protein) [NCBI Gene 1401] {aka PTX1}, GAST (gastrin) [NCBI Gene 2520] {aka GAS}, IL6 (interleukin 6) [NCBI Gene 3569] {aka BSF-2, BSF2, CDF, HGF, HSF, IFN-beta-2}, CCK (cholecystokinin) [NCBI Gene 885], Nos3 (nitric oxide synthase 3) [NCBI Gene 24600] {aka eNos}, TNF (tumor necrosis factor) [NCBI Gene 7124] {aka DIF, IMD127, TNF-alpha, TNFA, TNFSF2, TNLG1F}, MAPT (microtubule associated protein tau) [NCBI Gene 4137] {aka DDPAC, FTD1, FTDP-17, MAPTL, MSTD, MTBT1}
- **Diseases:** delayed-gastric-emptying syndrome (MESH:D013274), Parkinson's disease (MESH:D010300), abdominal discomfort (MESH:D000007), Alzheimer's (MESH:D000544), nausea, vomiting (MESH:D020250), liver injury (MESH:D017093), organ disease (MESH:D000092124), neuroinflammation (MESH:D000090862), heart failure (MESH:D006333), biliary complications (MESH:D008107), GI side effect (MESH:D064420), diarrhea (MESH:D003967), MACE (MESH:D002318), type two diabetes (MESH:D003922), blood pressure (MESH:D006973), acute pancreatitis (MESH:D010195), hypoglycemia (MESH:D007003), gallbladder disease (MESH:D005705), birth defects (MESH:D000014), vomiting (MESH:D014839), anaphylaxis (MESH:D000707), inflammation (MESH:D007249), neurodegenerative disease (MESH:D019636), Anterior Ischemic Optic Neuropathy (MESH:D018917), GI adverse effects (MESH:D005767), atherosclerosis (MESH:D050197), diabetes (MESH:D003920), biliary disease (MESH:D001660), biliary or gallstone disease (MESH:D002769), ovarian cancer (MESH:D010051), angioedema (MESH:D000799), medullary thyroid carcinoma (MESH:C536914), visceral adiposity (MESH:D007418), thyroid C-cell tumors (MESH:D013968), pancreatic, colorectal cancer (MESH:D015179), C-cell hyperplasia (MESH:D006965), metabolic disease (MESH:D008659), weight gain (MESH:D015430), blindness (MESH:D001766), neuronal destruction (MESH:D008105), Nausea (MESH:D009325), insulin resistance (MESH:D007333), dementia (MESH:D003704), dyslipidemia (MESH:D050171), multiple myeloma (MESH:D009101), stroke (MESH:D020521), gallstone (MESH:D042882), acute kidney injury (MESH:D058186), gastrointestinal (GI) symptoms (MESH:D012817), retinal toxicity (MESH:D012164), thyroid C-cell hyperplasia or carcinoma (MESH:D013964), gastroparesis (MESH:D018589), myocardial infarction (MESH:D009203), optic nerve disorder (MESH:D000080344), visual disturbances (MESH:D014786), metabolic disruption (MESH:D019958), impaired kidney function (MESH:D007674), tumorigenesis (MESH:D063646), cancer (MESH:D009369), weight (MESH:D015431)
- **Chemicals:** bicarbonate (MESH:D001639), glucose (MESH:D005947), lipid (MESH:D008055), triglycerides (MESH:D014280), potassium (MESH:D011188), cholesterol (MESH:D002784), GLP-1RAs (-), nitric oxide (MESH:D009569), calcium (MESH:D002118), sodium (MESH:D012964), sulfonylureas (MESH:D013453), blood glucose (MESH:D001786)
- **Species:** Homo sapiens (human, species) [taxon 9606], Rattus norvegicus (brown rat, species) [taxon 10116]

## Figures

4 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12981728/full.md

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Source: https://tomesphere.com/paper/PMC12981728