What it is
Semaglutide is a GLP-1 receptor agonist. It is a modified version of glucagon-like peptide-1 (GLP-1), a gut hormone, and it binds to and activates GLP-1 receptors.
How it works
- GLP-1 receptors are found in the pancreas, gut and brain. Activating them is involved in glucose-dependent insulin release, slower stomach emptying and appetite signaling [1].
- This page does not present clinical trial results. Trial results for approved products apply to those products, not to compounded semaglutide.
Regulatory status
FDA has approved separate semaglutide medicines for specific uses. Compounded semaglutide is not FDA approved, and FDA states unapproved versions do not undergo its review for safety, effectiveness and quality [2]. Where prescribed, compounded versions are prepared by state-licensed 503A compounding pharmacies.
Safety and side effects
The approved semaglutide label carries a boxed warning: in rodents, semaglutide causes thyroid C-cell tumors, and it is unknown whether it causes these tumors, including medullary thyroid carcinoma (MTC), in humans. The approved product is contraindicated in people with a personal or family history of MTC or with Multiple Endocrine Neoplasia syndrome type 2 (MEN 2) [1]. The label also warns about acute pancreatitis, acute gallbladder disease, low blood sugar when used with insulin or an insulin secretagogue, acute kidney injury due to volume depletion, severe gastrointestinal reactions, serious allergic reactions, diabetic retinopathy complications in people with type 2 diabetes, increased heart rate, and pulmonary aspiration during general anesthesia or deep sedation [1]. Its most common adverse reactions include nausea, diarrhea, vomiting, constipation, abdominal pain, headache, fatigue and dyspepsia [1]. FDA has received adverse event reports, some requiring hospitalization, that may be related to dosing errors with compounded injectable semaglutide, and recommends discarding a multiple-dose vial within 28 days after first use [2]. FDA says compounded drugs should only be used in patients whose medical needs cannot be met by an FDA-approved drug [2]. A licensed healthcare provider should review your history, medications and goals.
Is it right for you?
Only a licensed healthcare provider can decide whether any treatment is appropriate for you.
Frequently asked questions
Is compounded semaglutide approved by FDA?
No. FDA has approved separate semaglutide medicines, but compounded versions are not FDA approved [2].
What are the common side effects?
The approved label lists nausea, diarrhea, vomiting, constipation, abdominal pain, headache, fatigue and dyspepsia among the most common adverse reactions. It also carries a boxed warning about thyroid C-cell tumors seen in rodents [1].
Do I need a prescription for Semaglutide?
Yes. Prescription only, requires evaluation by a licensed provider. A provider decides whether it is appropriate for you.
Sources
- FDA prescribing information, WEGOVY (semaglutide) injection and tablets, revised 02/2026. https://www.accessdata.fda.gov/drugsatfda_docs/label/2026/215256s033lbl.pdf
- FDA: FDA's concerns with unapproved GLP-1 drugs. https://www.fda.gov/drugs/drug-alerts-and-statements/fdas-concerns-unapproved-glp-1-drugs-used-weight-loss
Semaglutide content on this page is for education. Compounded medications are not FDA approved. Prescription only, requires evaluation by a licensed provider. Educational content only, not medical advice.