Semaglutide

Metabolic & weight FDA-approved drug

GLP-1 receptor agonist · also known as Ozempic, Wegovy

For reference only — not medical advice. Figures are commonly reported values compiled from published sources and may be wrong or out of date. Many compounds listed are not approved for human use. Talk to a licensed clinician before using any compound.

Semaglutide is a GLP-1 receptor agonist widely studied for glucose regulation and appetite. Its long half-life supports once-weekly dosing, and research protocols typically escalate the dose gradually.

Commonly reported dosing by vial size

Frequency: Once weekly, subcutaneous · Half-life: ~7 days

Vial size (5 sizes)5 mg10 mg15 mg20 mg30 mg

5 mg vial + 2 mL → 2.5 mg per mL

Diluent: bacteriostatic water (as commonly reported)

The 5 mg vial is commonly reconstituted with 2 mL.

Commonly reported reconstitution steps

Vials are usually brought to room temperature (about 15-20 minutes) first.
2 mL of bacteriostatic water is added slowly down the inside wall of the 5 mg vial.
The vial is swirled gently until clear, not shaken.
This gives 2.5 mg/mL. Mixed vials are typically labeled with the date and refrigerated.

Commonly reported dosing

Phase	Dose	Volume	U-100 units
Starting Weeks 1-4	250 mcg	0.1 mL	10
Standard Weeks 9-12 in the studied schedule	1 mg	0.4 mL	40
Higher Weeks 13-16	1.7 mg	0.68 mL	68
Maintenance Week 17 onward	2.4 mg	0.96 mL	96

Commonly reported dose escalation

Weeks	Dose	Volume	U-100 units
Weeks 1-4	250 mcg	0.1 mL	10
Weeks 5-8	500 mcg	0.2 mL	20
Weeks 9-12	1 mg	0.4 mL	40
Weeks 13-16	1.7 mg	0.68 mL	68
Week 17+	2.4 mg	0.96 mL	96

Higher steps may need a larger vial or more than one draw. Escalation schedules vary; dosing decisions belong to a licensed clinician.

Open in calculator (5 mg + 2 mL)

10 mg vial + 3 mL → 3.33 mg per mL

Diluent: bacteriostatic water (as commonly reported)

The 10 mg vial is commonly reconstituted with 3 mL.

Commonly reported reconstitution steps

Vials are usually brought to room temperature (about 15-20 minutes) first.
3 mL of bacteriostatic water is added slowly down the inside wall of the 10 mg vial.
The vial is swirled gently until clear, not shaken.
This gives 3.33 mg/mL. Mixed vials are typically labeled with the date and refrigerated.

Commonly reported dosing

Phase	Dose	Volume	U-100 units
Starting Weeks 1-4	250 mcg	0.075 mL	7.5
Standard Weeks 9-12 in the studied schedule	1 mg	0.3 mL	30
Higher Weeks 13-16	1.7 mg	0.51 mL	51
Maintenance Week 17 onward	2.4 mg	0.72 mL	72

Commonly reported dose escalation

Weeks	Dose	Volume	U-100 units
Weeks 1-4	250 mcg	0.075 mL	7.5
Weeks 5-8	500 mcg	0.15 mL	15
Weeks 9-12	1 mg	0.3 mL	30
Weeks 13-16	1.7 mg	0.51 mL	51
Week 17+	2.4 mg	0.72 mL	72

Higher steps may need a larger vial or more than one draw. Escalation schedules vary; dosing decisions belong to a licensed clinician.

Open in calculator (10 mg + 3 mL)

15 mg vial + 3 mL → 5 mg per mL

Diluent: bacteriostatic water (as commonly reported)

The 15 mg vial is commonly reconstituted with 3 mL.

Commonly reported reconstitution steps

Vials are usually brought to room temperature (about 15-20 minutes) first.
3 mL of bacteriostatic water is added slowly down the inside wall of the 15 mg vial.
The vial is swirled gently until clear, not shaken.
This gives 5 mg/mL. Mixed vials are typically labeled with the date and refrigerated.

Commonly reported dosing

Phase	Dose	Volume	U-100 units
Starting Weeks 1-4	250 mcg	0.05 mL	5
Standard Weeks 9-12 in the studied schedule	1 mg	0.2 mL	20
Higher Weeks 13-16	1.7 mg	0.34 mL	34
Maintenance Week 17 onward	2.4 mg	0.48 mL	48

Commonly reported dose escalation

Weeks	Dose	Volume	U-100 units
Weeks 1-4	250 mcg	0.05 mL	5
Weeks 5-8	500 mcg	0.1 mL	10
Weeks 9-12	1 mg	0.2 mL	20
Weeks 13-16	1.7 mg	0.34 mL	34
Week 17+	2.4 mg	0.48 mL	48

Higher steps may need a larger vial or more than one draw. Escalation schedules vary; dosing decisions belong to a licensed clinician.

Open in calculator (15 mg + 3 mL)

20 mg vial + 3 mL → 6.67 mg per mL

Diluent: bacteriostatic water (as commonly reported)

The 20 mg vial is commonly reconstituted with 3 mL.

Commonly reported reconstitution steps

Vials are usually brought to room temperature (about 15-20 minutes) first.
3 mL of bacteriostatic water is added slowly down the inside wall of the 20 mg vial.
The vial is swirled gently until clear, not shaken.
This gives 6.67 mg/mL. Mixed vials are typically labeled with the date and refrigerated.

Commonly reported dosing

Phase	Dose	Volume	U-100 units
Starting Weeks 1-4	250 mcg	0.037 mL	3.8
Standard Weeks 9-12 in the studied schedule	1 mg	0.15 mL	15
Higher Weeks 13-16	1.7 mg	0.255 mL	25.5
Maintenance Week 17 onward	2.4 mg	0.36 mL	36

Commonly reported dose escalation

Weeks	Dose	Volume	U-100 units
Weeks 1-4	250 mcg	0.037 mL	3.8
Weeks 5-8	500 mcg	0.075 mL	7.5
Weeks 9-12	1 mg	0.15 mL	15
Weeks 13-16	1.7 mg	0.255 mL	25.5
Week 17+	2.4 mg	0.36 mL	36

Higher steps may need a larger vial or more than one draw. Escalation schedules vary; dosing decisions belong to a licensed clinician.

Open in calculator (20 mg + 3 mL)

30 mg vial + 3 mL → 10 mg per mL

Diluent: bacteriostatic water (as commonly reported)

The 30 mg vial is commonly reconstituted with 3 mL.

Commonly reported reconstitution steps

Vials are usually brought to room temperature (about 15-20 minutes) first.
3 mL of bacteriostatic water is added slowly down the inside wall of the 30 mg vial.
The vial is swirled gently until clear, not shaken.
This gives 10 mg/mL. Mixed vials are typically labeled with the date and refrigerated.

Commonly reported dosing

Phase	Dose	Volume	U-100 units
Starting Weeks 1-4	250 mcg	0.025 mL	2.5
Standard Weeks 9-12 in the studied schedule	1 mg	0.1 mL	10
Higher Weeks 13-16	1.7 mg	0.17 mL	17
Maintenance Week 17 onward	2.4 mg	0.24 mL	24

Commonly reported dose escalation

Weeks	Dose	Volume	U-100 units
Weeks 1-4	250 mcg	0.025 mL	2.5
Weeks 5-8	500 mcg	0.05 mL	5
Weeks 9-12	1 mg	0.1 mL	10
Weeks 13-16	1.7 mg	0.17 mL	17
Week 17+	2.4 mg	0.24 mL	24

Higher steps may need a larger vial or more than one draw. Escalation schedules vary; dosing decisions belong to a licensed clinician.

Open in calculator (30 mg + 3 mL)

Storage

Before mixing: Sealed vials are commonly stored refrigerated (2-8 °C) and protected from light, or frozen for long-term storage.

After mixing: Reconstituted solution is commonly kept refrigerated (2-8 °C), protected from light, and not frozen.

Commonly used within 28 days of mixing.

How it works

By activating GLP-1 receptors, semaglutide enhances glucose-dependent insulin release, slows gastric emptying, and reduces appetite signaling in the brain.

Researched for

In STEP 1 (68 weeks, adults with overweight or obesity), mean weight change was -14.9% with 2.4 mg weekly versus -2.4% with placebo.
Studied extensively for glycemic control in type 2 diabetes.
Trial schedules escalate the dose gradually for gastrointestinal tolerability.

Notes

Gastrointestinal effects (nausea) are common early and usually ease with titration.
Trial and label schedules escalate the dose over weeks rather than beginning at the target amount.
The current Wegovy label lists weekly maintenance amounts of 1.7 or 2.4 mg, with a higher ceiling of 7.2 mg for some adults; the Ozempic label tops out at 2 mg weekly.
Reconstitution volumes of 2 mL (5 mg vials) and 3 mL (10-30 mg vials) are commonly reported.
Brand-name pens and kits are pre-measured; the reconstitution figures here apply to vials that require mixing.