Semaglutide Dose Calculator + Titration Schedule

Convert a reconstituted semaglutide vial into exact draw volumes (mL and U-100 IU), follow the standard titration schedule, and see a steady-state serum-concentration simulation. Also supports tirzepatide and retatrutide. Free, no sign-up.

Last updated: 2026-04-21 · Maintained by the VitaLog team

Standard titration schedule

GLP-1 receptor agonists require gradual dose escalation because the gastrointestinal side effects are dose-dependent. The FDA-label schedule from Novo Nordisk (both Ozempic and Wegovy) is:

Reconstitution math (compounded vials)

Compounded semaglutide ships as a lyophilized powder in 2 mg, 5 mg, or 10 mg vials. After adding bacteriostatic water, concentration = mass ÷ volume. Draw volume per dose = dose ÷ concentration.

5 mg vial + 1 mL BAC water (most common)

Concentration = 5 mg / 1 mL = 5 mg/mL = 5000 mcg/mL

Dose (mg)  | Volume (mL) | U-100 IU
-----------|-------------|---------
0.25       | 0.05        | 5
0.50       | 0.10        | 10
1.00       | 0.20        | 20
1.70       | 0.34        | 34
2.40       | 0.48        | 48

10 mg vial + 2 mL BAC water

Same concentration (5 mg/mL), same IU conversions. Gives twice as many doses per vial at the cost of a larger total BAC-water volume.

5 mg vial + 2 mL BAC water (lower concentration)

Concentration = 5 mg / 2 mL = 2.5 mg/mL = 2500 mcg/mL

Dose (mg)  | Volume (mL) | U-100 IU
-----------|-------------|---------
0.25       | 0.10        | 10
0.50       | 0.20        | 20
1.00       | 0.40        | 40
1.70       | 0.68        | 68  (may need two injections)
2.40       | 0.96        | 96  (use a 1-mL graduated syringe instead)

Use a higher concentration (less BAC water per mg) if your later doses would otherwise exceed the insulin-syringe capacity. Use a lower concentration for easier tick-mark resolution at low starting doses.

Pharmacokinetics (what's happening inside you)

Semaglutide absorbs slowly from subcutaneous tissue over 1-3 days, reaches peak serum concentration at 1-3 days post-injection, and is eliminated with a terminal half-life of approximately 7 days. That long half-life is the reason weekly dosing is sufficient, and the reason steady state takes about 5 weekly doses to reach at any new dose level.

Steady-state metrics (1 mg/week maintenance)

• Cmax (peak): approximately 55-75 ng/mL at steady state (interquartile range across published cohorts; see Granhall 2019, PMID 29722029)
• Cmin (trough): approximately 40-55 ng/mL
• Peak-to-trough ratio: relatively flat (~1.3-1.5×) because weekly dosing of a 7-day-half-life drug produces smooth accumulation
• Accumulation ratio: ~2× (τ ≈ t½ at weekly dosing of a 7-day half-life drug gives ratio = 1/(1 − e^−ln(2)) = 2.0 by the standard formula)
• Time to steady state: ~5 weeks (5 × 7-day half-life)

Steady-state pharmacokinetic values are summarized from the semaglutide clinical-pharmacology sections of the Ozempic and Wegovy prescribing information (Novo Nordisk). For single-dose pharmacokinetics including renal-impairment data, see Marbury TC, Flint A, Jacobsen JB, Derving Karsbøl J, Lasseter K. Clin Pharmacol Drug Dev. 2017;6(6):487-496. PMID: 28239807 (single-dose study, steady-state values above are from separate multi-dose trials).

Injection technique & site rotation

Subcutaneous (not intramuscular) injection with a short 27-30 gauge needle. Pinch a fold of skin, insert at 45-90°, inject slowly, withdraw. Common sites:

• Abdomen (≥5 cm lateral to the navel), most commonly used
• Anterior thigh (middle third)
• Posterior upper arm (deltoid/triceps interface)

Rotate sites each week. VitaLog's cycle tracker records the last site for each compound and flags the next scheduled site automatically.

Ozempic / Wegovy vs. compounded semaglutide

The active molecule is identical. Differences:

If switching between brands, always re-check your concentration math. The calculator handles any concentration, but you must enter the correct vial-size + BAC-water combination for the new vial.

Side-effect timing & mitigation

Nausea, vomiting, diarrhea, constipation, and appetite loss are very common, especially in the first 2-4 weeks of each dose step. They usually improve after a month at the same dose.

Mitigation that actually works

• Smaller, more frequent meals. Gastric emptying slows on GLP-1s; large meals amplify reflux and nausea.
• Low-fat, low-spice for the first week of each step. Fat delays gastric emptying further.
• Hydration. GLP-1s blunt thirst cues; actively drink water.
• Inject the evening before a non-work day. Peak side effects are day 2-3 post-injection for semaglutide.
• Stay at the lower dose longer. There is no clinical benefit to rushing up the ladder.

Frequently asked questions

What is the standard semaglutide titration schedule?

The standard FDA-label titration is 0.25 mg weekly for 4 weeks, then 0.5 mg weekly for 4 weeks, then 1.0 mg weekly for 4 weeks, then maintenance typically at 1.0-2.4 mg weekly. Each step gives the gastrointestinal side effects time to adapt before increasing the dose. Skipping steps increases nausea, vomiting, and early discontinuation.

How do I convert semaglutide mg to IU on an insulin syringe?

Depends on concentration. For a 5 mg vial reconstituted with 1 mL bacteriostatic water (concentration 5 mg/mL = 5000 mcg/mL), a 0.25 mg dose is 0.05 mL = 5 IU on a U-100 insulin syringe. Use VitaLog's calculator to get the exact IU for any concentration.

How long does it take to reach steady state?

Semaglutide has a terminal half-life of approximately 7 days, so steady state is reached after about 4-5 weekly doses (≈5 × t½). Expect the therapeutic effect to stabilize at each dose level after a month.

What is the trough serum concentration at 1 mg/week steady state?

Approximately 40-55 ng/mL at weekly trough (the day before the next injection), with Cmax at peak approximately 55-75 ng/mL. Values are summarized from the Ozempic / Wegovy clinical-pharmacology sections and Granhall et al. 2019 (PMID 29722029), which characterizes steady-state pharmacokinetics of subcutaneous semaglutide. VitaLog's PK simulator plots the full Cmax-Cmin envelope for any weekly dose.

Is compounded semaglutide the same as Ozempic or Wegovy?

The active molecule is the same, semaglutide. Compounded versions differ in concentration, reconstitution volume, inactive ingredients, manufacturing controls, and sometimes dose units (mg vs IU on the label). Always re-check your concentration math when switching between brands. Ozempic and Wegovy are prefilled pens from Novo Nordisk; compounded versions are reconstituted from a lyophilized vial.

Should I inject in the same site every time?

No, rotate. Subcutaneous injection into abdomen, thigh, or deltoid. Rotating prevents local irritation and improves absorption reliability. VitaLog's cycle tracker records the last-used site so you can rotate systematically.

What are the most common side effects during titration?

Nausea, vomiting, diarrhea, constipation, abdominal discomfort, and reduced appetite are most common, especially during the first 2-4 weeks of each dose-escalation step. Slowing titration (staying at a lower dose for an extra 2-4 weeks), eating smaller meals, and staying hydrated all help. Severe or persistent symptoms warrant consultation with a clinician.

Does VitaLog also support tirzepatide and retatrutide?

Yes. All three GLP-1 receptor agonists (semaglutide, tirzepatide, retatrutide) are in VitaLog's compound database with published pharmacokinetic parameters, titration schedules, and PK simulation models.

Can I use VitaLog to track my weekly dose?

Yes. The cycle tracker records every injection, dose, site, time, with dose-adherence streaks and injection-site rotation. The PK simulator shows your serum-concentration curve across the full week. All data is stored locally by default; optional cloud sync is end-to-end encrypted.

Is semaglutide safe?

Semaglutide is FDA-approved for type 2 diabetes (Ozempic) and chronic weight management (Wegovy). It carries a boxed warning for thyroid C-cell tumors based on rodent studies (human relevance debated) and is contraindicated in personal or family history of medullary thyroid carcinoma or MEN2. Pancreatitis, gallbladder disease, and hypoglycemia (when combined with insulin/sulfonylureas) are other notable risks. Not medical advice, consult a qualified healthcare professional.

Related resources

• General peptide dose calculator
• Pharmacokinetics explained for non-clinicians
• TRT bloodwork guide (relevant if you're on TRT + GLP-1 combination)