[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [GLP-1 receptor agonists](https://durgical.com/en/pharmacology/classes/glp-1-receptor-agonists/) › Semaglutide

[Pharmacology](https://durgical.com/en/pharmacology/) · [GLP-1 receptor agonists](https://durgical.com/en/pharmacology/classes/glp-1-receptor-agonists/)

# Semaglutide

A long-acting GLP-1 agonist, weekly by injection or daily by mouth: strong glucose lowering, large weight loss and fewer cardiovascular events.

Updated 2026-11-01

- Class: [GLP-1 receptor agonists](https://durgical.com/en/pharmacology/classes/glp-1-receptor-agonists/)
- Receptor: GLP-1 receptor (GLP1R)
- ATC code: A10BJ06
- WHO Model List of Essential Medicines

◎**GLP-1 receptor (GLP1R)**Semaglutide

ⓘ The figure shows semaglutide bound to the human GLP-1 receptor coupled to its Gs protein; the nanobody used to stabilize the complex is not part of the receptor.

**Target in 3D:** GLP-1 receptor (GLP1R). PDB structure 7KI0 (RCSB PDB, public domain). [View the structure at RCSB PDB](https://www.rcsb.org/structure/7KI0) · Drag to rotate · pinch to zoom

## Mechanism of action

Semaglutide is a GLP-1 analogue with an amino-acid change that blocks DPP-4 and a long fatty diacid chain that binds albumin strongly, giving a week-long action. On the GLP-1 receptor it increases glucose-dependent insulin release, lowers glucagon, slows gastric emptying and acts on appetite centers in the brain, which explains its large effect on weight.

- Activates the GLP-1 receptor (Gs, cAMP)
- Beta cells release more insulin when glucose is high
- Glucagon falls and the stomach empties more slowly
- Appetite falls: lower glucose and weight

## Pharmacokinetics

**Absorption**
Weekly subcutaneous injection; the oral tablet is absorbed in the stomach with the help of an absorption enhancer and needs an empty stomach.

**Distribution**
Almost entirely bound to albumin.

**Metabolism**
Broken down by peptidases and fatty-acid oxidation.

**Half-life**
Long, which allows once-weekly injection.

## Indications

- Type 2 diabetes, and to reduce heart attack, stroke and death in those with cardiovascular disease [Type 2 diabetes mellitus →](https://durgical.com/en/conditions/type-2-diabetes-mellitus/)
- Chronic weight management in obesity or overweight with weight-related conditions [Obesity →](https://durgical.com/en/conditions/obesity/)
- Type 2 diabetes with chronic kidney disease, to slow kidney decline [Chronic kidney disease →](https://durgical.com/en/conditions/chronic-kidney-disease/)

## Adverse effects

### Common

- Nausea, vomiting, diarrhea, constipation, abdominal pain (most common, mostly at the start)
- Reduced appetite
- Injection-site reactions
- Slightly faster heart rate

### Serious (rare, important)

- Acute pancreatitis
- Gallbladder disease (gallstones, cholecystitis)
- Acute kidney injury from dehydration after vomiting or diarrhea
- Thyroid C-cell tumors (seen in rodents; risk in humans unknown)
- Pulmonary aspiration during anesthesia or deep sedation, because the stomach empties slowly
- Worsening of diabetic retinopathy when glucose falls fast

## Contraindications

- Personal or family history of medullary thyroid carcinoma
- Multiple endocrine neoplasia type 2 (MEN 2)
- Serious hypersensitivity to the drug

## Key interactions

**Insulin or sulfonylureas**
Higher risk of hypoglycemia; their dose is often reduced.

**Oral drugs in general**
Slower gastric emptying can change their absorption.

## What is monitored

- HbA1c and weight
- Eye exams in people with diabetic retinopathy
- Kidney function if vomiting or diarrhea
- Symptoms of pancreatitis or gallbladder disease

## Administration and safety

- Subcutaneous injection in the abdomen, thigh or upper arm, rotating sites.
- Pens are for one person only and are never shared, even with a new needle.
- The dose is raised step by step to limit nausea.
- The oral tablet is taken on an empty stomach with a little water, waiting before eating or other medicines.

## Nursing care

- Before: thyroid history (medullary carcinoma, MEN 2), pancreatitis history, kidney function.
- During: severe abdominal pain spreading to the back (pancreatitis), vomiting and dehydration.
- Teach to report a neck lump, hoarseness or trouble swallowing.
- The anesthesia team is told before surgery or endoscopy.

## Pregnancy and breastfeeding

Not used in pregnancy (weight loss is not a goal and animal data showed harm); it is stopped ahead of a planned pregnancy.

## Memory aid

Semaglutide = 'seven-day GLP-1': one injection, one week. The stronger the brake on the stomach and appetite, the more the weight falls, and the more nausea at the start.

## Test yourself

Think of the answer, then tap the question to see it.

## What makes semaglutide last about a week?

A fatty diacid chain that binds albumin tightly, plus an amino-acid change that blocks DPP-4.

## Which eye problem can worsen when semaglutide lowers glucose quickly?

Diabetic retinopathy; people who already have it need eye follow-up.

## Before a semaglutide user has elective surgery, why should the anesthesia team know?

The drug slows gastric emptying, so the stomach may not be empty and the risk of aspiration rises.

## Which two benefits beyond glucose lowering has semaglutide shown?

Weight loss and fewer major cardiovascular events (heart attack, stroke, cardiovascular death) in people with cardiovascular disease; also slower kidney decline in diabetic kidney disease.

[Add to my cards (4)](https://durgical.app/estudiar/?add=/en/pharmacology/semaglutide/)

## Related drugs

- [Liraglutide](https://durgical.com/en/pharmacology/liraglutide/)
- [Dulaglutide](https://durgical.com/en/pharmacology/dulaglutide/)
- [Tirzepatide](https://durgical.com/en/pharmacology/tirzepatide/)
- [Exenatide](https://durgical.com/en/pharmacology/exenatide/)

## Related conditions

- [Type 2 diabetes mellitus](https://durgical.com/en/conditions/type-2-diabetes-mellitus/)
- [Obesity](https://durgical.com/en/conditions/obesity/)
- [Chronic kidney disease](https://durgical.com/en/conditions/chronic-kidney-disease/)

[← Back to the class: GLP-1 receptor agonists](https://durgical.com/en/pharmacology/classes/glp-1-receptor-agonists/)

Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.

Sources: [Semaglutide Injection: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a618008.html) (MedlinePlus (U.S. National Library of Medicine), 2026); [Semaglutide-bound Glucagon-Like Peptide-1 (GLP-1) Receptor in Complex with Gs protein](https://www.rcsb.org/structure/7KI0) (RCSB Protein Data Bank, 2021); [ATCDDD - ATC/DDD Index](https://atcddd.fhi.no/atc_ddd_index/?code=A10BJ06) (WHO Collaborating Centre for Drug Statistics Methodology, 2026); [eEML - Electronic Essential Medicines List](https://list.essentialmeds.org/) (World Health Organization, 2025).

## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake

Representative model, for educational purposes only.

---
Source: https://durgical.com/en/pharmacology/semaglutide/
License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/semaglutide/