Semaglutide Guide
Semaglutide is a GLP-1 receptor agonist approved by the FDA for both type 2 diabetes management and chronic weight management. It has become one of the most prescribed medications in the United States, with clinical trials demonstrating weight loss of up to 15% of body weight.
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At a Glance
How Semaglutide Works
Semaglutide mimics the naturally occurring hormone GLP-1 (glucagon-like peptide-1), which is released after eating. It activates GLP-1 receptors in the brain to reduce appetite and increase feelings of fullness, while also slowing gastric emptying so food stays in the stomach longer. These combined effects lead to reduced caloric intake and meaningful, sustained weight loss.[3][6]
Dosing Schedule
Semaglutide uses a gradual dose escalation to minimize side effects. Always follow your prescriber's guidance and the current FDA label[1].
Side Effects
Common: nausea, vomiting, diarrhea, constipation, abdominal pain, decreased appetite, headache, fatigue. Serious (rare): pancreatitis, gallbladder disease, kidney problems, diabetic retinopathy complications, increased heart rate. Rare thyroid C-cell tumors observed in animal studies — contraindicated in patients with personal or family history of MTC or MEN2.[1][3]
Nothing above is the full list. Your prescriber can give you the complete safety picture, and every adverse reaction on record sits in the current FDA prescribing information[1].
Clinical Trial Results
In the landmark STEP-1 trial (N=1,961), adults treated with semaglutide 2.4mg achieved an average body weight loss of 14.9% over 68 weeks, compared to 2.4% in the placebo group. 86.4% of participants lost at least 5% of body weight, versus 31.5% with placebo.[3][4][5]
Where to Get Semaglutide
Sellers in our register that will dispense semaglutide, or a compounded version of it, after an online consultation — shipped to your door.
Trimi Health
Best for: knowing which pharmacy fills the vial — it names VialsRx
Editorial score · methodology
Editorial score · methodology
Editorial score · methodology
Editorial score · methodology
Editorial score · methodology
Editorial score · methodology
Cost Comparison
What each seller in the register charges to start on a compounded GLP-1, cheapest at the top. Compounded semaglutide from licensed 503A and 503B pharmacies is legal under federal compounding law[7], and the rules have historically loosened further for any molecule sitting on the FDA Drug Shortage List[8]. An FSA or HSA will generally cover either kind of prescription, compounded or branded, under IRS Publication 502[9]. What you actually pay moves with your dose and with whatever promotion happens to be running.
Semaglutide Head-to-Head Comparisons
Short verdict pages setting Semaglutide against the other GLP-1 options, working from the trial results, the dose ladders on each label, and what the manufacturers charge today.
See all drug-vs-drug verdicts.
Pivotal Semaglutide Trial Walkthroughs
The trials that produced the Semaglutide label, taken endpoint by endpoint, with the figures read off the source.
Semaglutide Patient Questions, Answered
Questions people actually asked about Semaglutide in named subreddits, each answered from the published trial data.
Semaglutide Reference Cards
One-screen references for the dose schedule, what to do about a missed dose, and the side effects that warrant a call. Every figure checked against the DailyMed label.
Ranked PubMed Studies on Semaglutide
The peer-reviewed studies on Semaglutide and its neighbours that carry the most weight, gathered into lists. Every PMID was checked against PubMed esummary rather than recalled.
Related Research on Semaglutide
Longer pieces written here, built on the trial papers themselves, checked against the FDA label, and argued rather than summarized.
Frequently Asked Questions
Sources & methodology — as of August 2026
- 1.FDA — Wegovy (semaglutide) Approval History via Drugs@FDA— U.S. Food & Drug Administration.
- 2.FDA — Ozempic (semaglutide) Prescribing Information via Drugs@FDA— U.S. Food & Drug Administration.
- 3.STEP 1 Trial — Once-Weekly Semaglutide in Adults with Overweight or Obesity (Wilding JPH et al.)— New England Journal of Medicine.PMID: 33567185.
- 4.SURMOUNT-5 Trial — Tirzepatide vs. Semaglutide Head-to-Head in Obesity (Garvey WT et al.)— New England Journal of Medicine.PMID: 40334173.
- 5.SELECT Trial — Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes (Lincoff AM et al.)— New England Journal of Medicine.PMID: 37952131.
- 6.ADA — Standards of Care in Diabetes (2025)— American Diabetes Association.
- 7.FDA — Compounding and the 503A Pharmacy Framework— U.S. Food & Drug Administration.
- 8.FDA — Drug Shortages Database (current shortage listings)— U.S. Food & Drug Administration.
- 9.IRS Publication 502 — Medical and Dental Expenses (HSA/FSA eligibility)— Internal Revenue Service.
Glossary
The words sellers use, defined. Tap any term.
- Wegovy · Drugs and brands
- Ozempic · Drugs and brands
- Rybelsus · Drugs and brands
- GLP-1 receptor · Mechanism
- STEP-1 · Major trials
- SELECT · Major trials
- Compounded GLP-1 · Pharmacy and drug forms
- Titration · Dosing