Compound Reference Overview
| Field | Value |
|---|---|
| Name | Semaglutide |
| Reference Code | GLP-1SG |
| Category | GLP-1 Receptor Agonist |
| Example Strengths | 2 mg, 5 mg, 10 mg (varies by formulation and manufacturer) |
| Reference Range | 0.25 mg – 2.4 mg once weekly (reported in published clinical trials; indication-dependent) |
| Frequency | Once weekly (subcutaneous administration in approved clinical use) |
| Key Safety Warning | Boxed Warning: Risk of thyroid C-cell tumors observed in rodent studies. Contraindicated in patients with personal or family history of medullary thyroid carcinoma (MTC) or Multiple Endocrine Neoplasia syndrome type 2 (MEN2). |
Mechanism of Action (Educational)
Semaglutide is a long-acting glucagon-like peptide-1 (GLP-1) receptor agonist. It binds to and activates the GLP-1 receptor, a G-protein-coupled receptor involved in glucose-dependent insulin secretion, appetite regulation, and gastric motility.
Activation of GLP-1 receptors enhances glucose-dependent insulin release, suppresses inappropriate glucagon secretion, delays gastric emptying, and reduces central appetite signaling through hypothalamic pathways.
Semaglutide has structural modifications that increase albumin binding and resistance to enzymatic degradation by DPP-4, resulting in an extended half-life and enabling once-weekly dosing.
Indications (Literature)
- Type 2 diabetes mellitus (glycemic control)
- Chronic weight management in adults with obesity or overweight with comorbidities
- Cardiovascular risk reduction in patients with type 2 diabetes and established cardiovascular disease
Administration (Literature)
| Parameter | Details |
|---|---|
| Route | Subcutaneous (abdomen, thigh, or upper arm) |
| Frequency | Once weekly |
| Injection Sites | Abdomen, thigh, or upper arm (rotate sites) |
| Timing | Administered once weekly on the same day each week; may be taken with or without meals |
Pharmacokinetics (Literature)
Semaglutide has an approximate half-life of ~7 days, supporting once-weekly administration. Peak plasma concentrations are typically achieved within 1–3 days after subcutaneous injection.
The molecule is highly albumin-bound, reducing renal clearance and enzymatic degradation. Steady-state concentrations are generally reached after 4–5 weeks of weekly dosing.
Metabolism occurs through proteolytic cleavage of the peptide backbone and beta-oxidation of the fatty acid side chain. Excretion occurs via urine and feces as metabolized fragments.
Titration Schedule (Literature)
Gradual dose escalation is recommended in clinical practice to minimize gastrointestinal adverse effects.
Typical titration schedule (indication-dependent):
- 0.25 mg once weekly for 4 weeks (initiation dose)
- 0.5 mg once weekly for at least 4 weeks
- May increase to 1.0 mg weekly (diabetes indication)
- For weight management, may escalate incrementally to 2.4 mg weekly
Dose adjustments should be individualized based on tolerability and therapeutic response.
Reconstitution & Concentration (Mathematical Illustration Only)
The following reconstitution example applies to compounded formulations and is provided strictly for mathematical illustration. It does not represent prescribing guidance.
| Parameter | Value |
|---|---|
| Diluent | Bacteriostatic water (example only) |
| Reconstitution Volume | 2 mL (example only) |
| Resulting Concentration | 5 mg/mL (5000 mcg/mL) |
| Stability | Varies by formulation and compounding standards; follow manufacturer guidance |
Reconstitution Math Example
Example calculation:
10 mg ÷ 2 mL = 5 mg/mL
This example is provided strictly to demonstrate arithmetic concentration calculations and does not imply dosing or treatment recommendations.
Safety & Contraindications (Summary)
Contraindications
- Personal or family history of medullary thyroid carcinoma (MTC)
- Multiple Endocrine Neoplasia syndrome type 2 (MEN2)
- Known hypersensitivity to semaglutide or formulation components
Adverse Events
- Nausea
- Vomiting
- Diarrhea
- Constipation
- Decreased appetite
Serious Adverse Events
- Pancreatitis (rare but reported)
- Gallbladder disease
- Acute kidney injury (usually secondary to dehydration)
- Diabetic retinopathy complications (in high-risk patients)
Drug Interactions
- May delay gastric emptying, potentially affecting absorption of oral medications
- Caution with insulin or sulfonylureas due to hypoglycemia risk
Monitoring (Literature)
- HbA1c (every 3 months in diabetes management)
- Fasting glucose levels
- Body weight and BMI
- Renal function (if significant GI symptoms occur)
- Symptoms suggestive of pancreatitis or gallbladder disease
Mathematical Calculation Tool
The calculator below allows mathematical concentration and volume calculations using variable vial strengths and reconstitution volumes. This tool is provided strictly for arithmetic reference.
Peptide Reconstitution Calculator
For Educational & Professional Reference Only
Disclaimer
This content is provided strictly as a pharmacologic and mathematical reference for educational and professional purposes. It does not constitute medical advice, prescribing guidance, diagnosis, or treatment recommendations. All clinical decisions must be made by a licensed healthcare professional in accordance with applicable regulations.
Reference Sources
1. Lau J, et al. Discovery of the Once-Weekly GLP-1 Analogue Semaglutide.
J Med Chem. 2015; PMID: 26308095.
2. Yang XD, Yang YY. Clinical Pharmacokinetics of Semaglutide.
Drug Des Devel Ther. 2024; PMID: 38952487.
3. Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity.
N Engl J Med. 2021; PMID: 33567185.