Compounds / Semaglutide
Semaglutide
Also known as: Development codes NN9535 (subcutaneous) and NN9924 / OG217SC (oral); CAS 910463-68-2
Primary research focus: Type 2 diabetes, chronic weight management, and cardiovascular / kidney risk reduction (metabolic)
Last updated July 2026 · Reviewed against FDA labeling and published research.
What is Semaglutide?
Semaglutide is a GLP-1 receptor agonist marketed by Novo Nordisk as Ozempic and Rybelsus (type 2 diabetes) and as Wegovy (chronic weight management). It is available as a once-weekly subcutaneous injection and as a once-daily oral tablet. It improves glycemic control, reduces appetite and food intake, and has been shown to lower the risk of major adverse cardiovascular events in specific populations.
Selective agonist at the glucagon-like peptide-1 (GLP-1) receptor. It increases glucose-dependent insulin secretion, suppresses glucagon, and slows gastric emptying, and it acts on central appetite centers to reduce hunger and food intake. A C18 fatty diacid side chain binds serum albumin, which slows renal clearance and extends the half-life to support once-weekly subcutaneous dosing.
How it’s supplied
Brand / trade names: Ozempic, Wegovy, Rybelsus
Marketed by Novo Nordisk as Ozempic (subcutaneous, type 2 diabetes and cardiovascular / kidney risk reduction), Rybelsus (oral tablets, type 2 diabetes and cardiovascular risk reduction), and Wegovy (subcutaneous for chronic weight management, cardiovascular risk reduction, and noncirrhotic MASH; also an oral 25 mg tablet for chronic weight management approved in December 2025). Injectable forms are supplied as ready-to-use prefilled pens and single-dose vials; oral forms as tablets. Approved products are not reconstituted by the patient. Broad compounded semaglutide is no longer generally available after the FDA resolved the shortage (see US regulatory status).
Dosage Chart
Units shown are for a U-100 insulin syringe (100 units = 1 mL), calculated from the vial size and BAC water you select. Always confirm against your prescription and your syringe markings.
| Phase | Dose | Frequency | Notes |
|---|---|---|---|
| Weeks 1-4 | 0.25mg | 1x Weekly | — |
| Weeks 5-8 | 0.5mg | 1x Weekly | — |
| Weeks 9-12 | 1.0mg | 1x Weekly | — |
| Weeks 13-16 | 1.7mg | 1x Weekly | — |
| Weeks 17+ | 2.4mg | 1x Weekly | — |
- Administer on the same day each week to maintain stable plasma levels
- Titrate slowly; gastrointestinal effects are dose-related and ease with gradual escalation
- Rotate injection sites to reduce irritation and lipohypertrophy
- Reduce dose when combined with insulin or sulfonylureas to lower hypoglycemia risk
- Discuss pausing before scheduled surgery or anesthesia (delayed gastric emptying)
- Maintain hydration to offset gastrointestinal fluid loss
- Not for use during pregnancy or breastfeeding
- Do not exceed the recommended dose to try to speed results
Potential Benefits and Side Effects
Effects reported in published research. Not a promise of results, and not medical advice.
- Improved glycemic control (HbA1c reduction) in type 2 diabetes.
- Significant weight reduction in obesity and overweight trials (STEP program).
- Reduction in major adverse cardiovascular events in specific populations (SUSTAIN-6, SELECT, SOUL).
- Reduction in kidney disease progression and related outcomes in type 2 diabetes with chronic kidney disease (FLOW).
- Improvement in noncirrhotic MASH and fibrosis reported in trials (ESSENCE).
- Nausea.
- Diarrhea.
- Vomiting.
- Constipation.
- Abdominal pain.
- Decreased appetite.
- Injection-site reactions (injectable forms).
- Fatigue.
- Hypersensitivity reactions (less common).
- Gastrointestinal effects are most common during dose escalation.
Warnings and contraindications
Important safety information. This is not exhaustive — read the full prescribing information and consult your prescriber or pharmacist.
- Boxed warning: risk of thyroid C-cell tumors. Semaglutide caused thyroid C-cell tumors in rodents; human relevance is unknown.
- Pancreatitis: acute pancreatitis has been reported; discontinue if suspected.
- Acute gallbladder disease (cholelithiasis, cholecystitis) has been reported; evaluate if suspected.
- Hypoglycemia: increased risk when used with insulin or insulin secretagogues (e.g., sulfonylureas); a dose reduction of the concomitant agent may be needed.
- Acute kidney injury: reported, usually in the setting of dehydration from nausea, vomiting, or diarrhea.
- Diabetic retinopathy complications may occur in patients with type 2 diabetes; monitor as clinically indicated.
- Hypersensitivity reactions, including anaphylaxis and angioedema, have been reported; discontinue if they occur.
- Suicidal behavior and ideation: monitor for depression or suicidal thoughts (labeled precaution for the weight-management indication).
- Pregnancy: may cause fetal harm based on animal data; discontinue in advance of a planned pregnancy per labeling.
- Do not use with other semaglutide-containing products or any other GLP-1 receptor agonist.
- Personal or family history of medullary thyroid carcinoma (MTC).
- Multiple Endocrine Neoplasia syndrome type 2 (MEN 2).
- Known serious hypersensitivity to semaglutide or any excipient in the product.
Reconstitution Steps
How to prepare the lyophilized vial. Confirm specifics with your pharmacist or prescriber.
- Confirm the vial strength on the label and the diluent volume specified by your pharmacy or prescription before starting.
- Wash your hands and gather supplies: the powder vial, the prescribed diluent (typically bacteriostatic water), an alcohol swab, and a sterile syringe.
- Let the powder vial and diluent reach room temperature if they were refrigerated.
- Wipe the rubber stopper of both the powder vial and the diluent vial with a fresh alcohol swab and let them air dry.
- Draw the exact diluent volume specified by your pharmacy into the syringe.
- Insert the needle into the powder vial and slowly release the diluent down the inside wall of the vial rather than directly onto the powder.
- Do not shake. Gently swirl or roll the vial until the powder is fully dissolved.
- Inspect the solution: it should be clear and colorless with no visible particles. Do not use if cloudy, discolored, or containing particles.
- Note the resulting concentration (vial strength divided by the diluent volume) so it matches the reconstitution calculator on this page.
- Label the vial with the reconstitution date and store as directed under reconstituted storage.
US regulatory status
Classifications are public record but can change. For reference only, not legal advice.
Development: Ozempic (subcutaneous) was FDA approved in December 2017 for type 2 diabetes, with later additions for reducing major adverse cardiovascular events in type 2 diabetes with established cardiovascular disease and, in January 2025, for reducing the risk of sustained eGFR decline, end-stage kidney disease, and cardiovascular death in type 2 diabetes with chronic kidney disease. Rybelsus (oral) was approved in 2019 for type 2 diabetes and in October 2025 for cardiovascular risk reduction (SOUL trial). Wegovy (subcutaneous) was approved in June 2021 for chronic weight management, extended to adolescents 12 and older in December 2022, approved for cardiovascular risk reduction in March 2024 (SELECT trial), and received accelerated approval for noncirrhotic metabolic dysfunction-associated steatohepatitis (MASH) with fibrosis. An oral semaglutide 25 mg tablet (Wegovy) was approved in December 2025 for chronic weight management (OASIS 4). Manufactured by Novo Nordisk.
Notes: The FDA determined the semaglutide injection shortage resolved on February 21, 2025. Enforcement discretion for 503A state-licensed pharmacies ended April 22, 2025, and for 503B outsourcing facilities on May 22, 2025; the district court denied the plaintiffs' preliminary injunction on April 24, 2025 (Outsourcing Facilities Association v. FDA). Semaglutide is not on FDA's drug shortage list or the 503B bulks list, so routine essentially-a-copy compounding is not permitted. A narrow 503A pathway remains only for an individual patient with a valid prescription and a documented clinical need the commercial product cannot meet (for example an excipient allergy or a strength not commercially available); cost savings and insurance access do not qualify. Salt forms such as semaglutide sodium or acetate were never the approved active ingredient. On April 30, 2026 the FDA proposed a rule to formally exclude semaglutide, tirzepatide, and liraglutide from the 503B bulks list on a finding of no clinical need (public comment period through June 29, 2026).
International status
Pharmacokinetics
Storage and handling
Important Notes
Practical considerations for consistency and safety.
- Ozempic, Wegovy, and Rybelsus all contain semaglutide; the brand determines the FDA-approved indication.
- The formulations are not milligram-for-milligram interchangeable, especially oral versus injectable; do not switch products without prescriber guidance.
- Rotate injection sites (abdomen, thigh, or upper arm) with each dose.
- Oral tablets are taken on an empty stomach with no more than about 4 ounces of plain water, at least 30 minutes before other food, drink, or oral medications.
- Compounded or research-grade semaglutide is not the FDA-approved finished drug and has not undergone FDA review for safety, potency, or sterility.
Lifestyle Factors
- Approved for use together with a reduced-calorie diet and increased physical activity for weight management.
- Adequate hydration can reduce the risk of dehydration-related complications during GI side effects.
- Alcohol may increase hypoglycemia risk, particularly with concomitant insulin or secretagogues.
- For the oral tablet, follow the fasted-administration requirement for reliable absorption.
References
Related compounds
Important disclaimer
This page is an educational reference, not medical advice, a diagnosis, or a treatment recommendation, and not a substitute for your prescriber or pharmacist. Approval and regulatory status varies by compound and can change. Always confirm against current prescribing information and consult a qualified healthcare professional before making any decision about a medication.