Description
Semaglutide is a GLP-1 receptor agonist and the most extensively studied compound in the GLP-1 family. Structurally it is a modified human GLP-1 analog with a fatty acid side chain that improves albumin binding and extends the half-life to approximately 7 days. This property makes it the reference compound for weekly application frequencies in research settings.
In research models, semaglutide activates the GLP-1 receptor in pancreatic beta cells, in the brain and in the gastrointestinal tract. Central mechanisms include delayed gastric emptying, enhanced satiety signaling in the hypothalamus and glucose-dependent insulin secretion. The large STEP trials documented average body weight reduction of approximately 15 percent over 68 weeks at highest dose.
Compared to dual or triple agonists in the family (tirzepatide, retatrutide), semaglutide acts on a single receptor. This makes it a clean research tool when the GLP-1 pathway is to be studied in isolation, without confounding through GIP or glucagon activation.
In research setups, semaglutide is typically started at low concentrations and increased weekly to minimize nausea effects. The half-life allows once-weekly application with consistent plasma levels.
Semaglutide is available in 5mg and 10mg vials, each as 10-vial packs.
This information is for research and educational purposes only. No medical recommendations.
Risks & Safety
Semaglutide is the most extensively studied compound in the GLP-1 family and is considered generally well tolerated per study reports. As a pure GLP-1 agonist the documented profile is clearly defined and dominated by gastrointestinal effects.
Observed in studies and user reports:
- Gastrointestinal effects: nausea, vomiting, diarrhea and constipation are the most commonly documented observations, particularly at the start and during the titration phase. In the STEP trials these are markedly reduced by slow titration.
- Appetite and fluids: the reduced appetite can lead to decreased food and fluid intake, and the literature describes an elevated risk of dehydration.
- Muscle mass: weight loss in studies involves a portion of muscle mass alongside fat mass.
- Gallbladder and injection site: gallbladder issues during rapid weight loss as well as mild irritation at the injection site are documented.
- Long-term data: despite the broad clinical data base, data on use beyond very long periods are lacking.
This classification does not replace medical advice. Risk and responsibility for any actual use lie entirely with the buyer.
Studies
- Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1) - NEJM 2021: Landmark trial with 1961 participants over 68 weeks.
- Effect of Subcutaneous Semaglutide vs Placebo as an Adjunct to Intensive Behavioral Therapy on Body Weight (STEP 3) - JAMA 2021: Data on lifestyle combination effects.
- Semaglutide and Cardiovascular Outcomes in Patients with Type 2 Diabetes (SUSTAIN-6) - NEJM 2016: Cardiovascular endpoints over 104 weeks.
- Tirzepatide versus Semaglutide Once Weekly in Patients with Type 2 Diabetes (SURPASS-2) - NEJM 2021: Direct head-to-head comparison.
