Semaglutide GLP-1 SM Dosage Protocols: All Vial Sizes
Semaglutide is a long-acting GLP-1 receptor agonist studied in landmark Phase 3 trials (STEP, SUSTAIN). Standard maintenance for weight protocols is 2.4 mg weekly. Choose your vial size below; each size has its own exact dosing table.
Choose Your Vial Size
| Vial | Final volume | Concentration | One U-100 unit | |
|---|---|---|---|---|
| 5 mg | 2 mL | 2.5 mg/mL | 25 mcg in 0.01 mL | Open protocol → |
| 10 mg | 3 mL | 3.33 mg/mL | 33.33 mcg in 0.01 mL | Open protocol → |
| 20 mg | 3 mL | 6.67 mg/mL | 66.67 mcg in 0.01 mL | Open protocol → |
Doses are the same research amounts across sizes; the vial size changes the concentration, so syringe units differ. Always use the table for your exact vial.
Storage Instructions
| State | Temperature | Duration |
|---|---|---|
| Lyophilized | −20°C (−4°F) | Up to 24 months, dry & dark |
| Reconstituted | 2–8°C (35–46°F) | Up to 28 days, protect from light |
Important Notes
How This Works
Semaglutide is a 31-amino-acid synthetic analog of native GLP-1. Two modifications give it a half-life of ~7 days vs minutes for native GLP-1: substitution of alanine at position 8 (preventing DPP-4 degradation) and a fatty-acid linker that binds albumin.
It activates GLP-1 receptors in pancreatic beta cells (enhancing insulin secretion), the hypothalamus (suppressing appetite), and the gut (slowing gastric emptying). Insulin response is glucose-dependent, so hypoglycemia risk is low as monotherapy.
Potential Benefits & Side Effects
Potential Benefits
- STEP-1: 14.9% body-weight reduction at 2.4 mg weekly over 68 weeks vs 2.4% placebo.
- SUSTAIN-6: 26% reduction in major cardiovascular events in T2DM with established CVD.
- HbA1c reductions of 1.5–1.8% across SUSTAIN program.
- Improvements in blood pressure and lipid profile.
Side Effect Profile
- Nausea (most common — usually mild during titration).
- Vomiting and diarrhea, particularly during dose escalation.
- Constipation in some users.
- Decreased appetite (intended).
- Rare: pancreatitis, gallbladder events.
Lifestyle Factors
- Hydrate aggressively — GLP-1 agonists blunt thirst.
- Protein 1.0–1.6 g/kg/day to preserve lean mass.
- Resistance training 2–3×/week.
- Limit high-fat meals during the first 24 hours after dosing.
- Smaller, more frequent meals; avoid eating to fullness.
Injection Technique
- Inject subcutaneously into abdomen, outer thigh, or upper arm — rotate weekly.
- Avoid 2-inch radius around navel.
- 90° angle with short (4–8 mm) insulin needles.
- Bring vial to room temperature 15 min before injecting.
- Hold 5–10 seconds after full plunger depression.