Last updated: May 2026
This guide covers the dose escalation schedule for compounded semaglutide, how to calculate draw volume from a vial, injection preparation, and common questions. It is a mathematical and procedural reference — not medical advice. Always follow your prescriber's specific instructions.
Need to convert your dose to mL? Use the calculator to get exact draw volumes and U-100 syringe units for any vial concentration.
Open Calculator →Semaglutide is a GLP-1 receptor agonist used in the treatment of type 2 diabetes and obesity. It mimics the glucagon-like peptide-1 hormone, which promotes insulin secretion, slows gastric emptying, and reduces appetite. Compounded semaglutide is produced by compounding pharmacies and supplied in multi-dose vials rather than pre-filled pens. The vials must be drawn from using an insulin syringe, which requires knowing the vial concentration to calculate the correct draw volume.
Compounded preparations are not FDA-approved finished drug products. They are subject to separate regulatory frameworks and are typically prescribed when brand-name products are unavailable or to meet specific clinical needs.
Semaglutide is titrated upward over several months to allow the body to adjust to the medication. The following schedule reflects commonly used escalation steps — your prescriber may adjust timing or increments based on your individual response and tolerability:
| Week | Dose | Notes |
|---|---|---|
| 1–4 | 0.25 mg/week | Starting dose — tolerance development |
| 5–8 | 0.5 mg/week | First increase if tolerated |
| 9–12 | 1.0 mg/week | Continue if tolerating well |
| 13–16 | 1.7 mg/week | Optional intermediate step |
| 17+ | 2.4 mg/week | Typical maximum maintenance dose |
Common side effects during escalation include nausea, vomiting, and diarrhoea — these often improve within a few weeks. If side effects are significant, some prescribers recommend extending each dose level for an additional 4 weeks before increasing.
Compounded semaglutide vials state concentration in mg/mL on the label. The draw volume calculation is straightforward:
Draw (mL) = Dose (mg) ÷ Concentration (mg/mL)
Concentration: 5 mg/mL
Dose: 0.5 mg
Draw = 0.5 ÷ 5 = 0.10 mL = 10 units (U-100 syringe)
On a U-100 insulin syringe, 1 unit = 0.01 mL. Multiply the draw in mL by 100 to get units. Use the InjectBuddy calculator to compute this automatically for any dose and concentration.
Calculate draw volume and U-100 units for any semaglutide dose and vial concentration.
Semaglutide Calculator →| Dose | 2.5 mg/mL vial | 5 mg/mL vial | 10 mg/mL vial |
|---|---|---|---|
| 0.25 mg | 0.10 mL (10 U) | 0.05 mL (5 U) | 0.03 mL (3 U) |
| 0.5 mg | 0.20 mL (20 U) | 0.10 mL (10 U) | 0.05 mL (5 U) |
| 1.0 mg | 0.40 mL (40 U) | 0.20 mL (20 U) | 0.10 mL (10 U) |
| 1.7 mg | 0.68 mL (68 U) | 0.34 mL (34 U) | 0.17 mL (17 U) |
| 2.4 mg | 0.96 mL (96 U) | 0.48 mL (48 U) | 0.24 mL (24 U) |
Compounded semaglutide vials should be stored in the refrigerator (2–8°C / 36–46°F). Do not freeze. Some preparations may be stable at room temperature for a limited period — check with your pharmacy for specific guidance on your product. Protect from light. Check the expiry date on the label before each injection.
Compounded semaglutide vials can vary because pharmacies may source and prepare different semaglutide forms and concentrations. Brand-name pens use a finished, manufacturer-controlled formulation. Multi-dose compounded vials are labelled by concentration, such as 2.5 mg/mL, 5 mg/mL, or 10 mg/mL, and the dose you draw depends entirely on that label.
Some compounded products have historically been described as semaglutide base, semaglutide sodium, or semaglutide acetate. These terms matter because salt forms can differ by molecular weight and potency assumptions. Do not convert between forms yourself. Use the concentration printed on your dispensed vial, confirm whether the label reports semaglutide-equivalent strength, and ask the pharmacy or prescriber if the wording is unclear.
If a weekly semaglutide dose is missed, many labelled protocols advise taking it as soon as remembered if the missed dose is within 5 days. If more than 5 days have passed, skip the missed dose and take the next dose on the normal scheduled day. Do not double the next injection to "catch up" unless your prescriber specifically tells you to.
Compounded protocols may differ, especially during dose escalation or after side effects. If repeated missed doses occur, ask your prescriber whether to restart at a lower dose or hold the current level longer before increasing.
Nausea is common during GLP-1 escalation. Practical steps that may help include taking the injection before bed, eating smaller meals, slowing down meal size increases, avoiding high-fat meals around dose day, and staying hydrated. Vomiting, persistent diarrhoea, severe abdominal pain, dehydration, or symptoms that do not settle should be discussed with a prescriber promptly.
Rotate injection sites between the abdomen, thigh, and upper arm to reduce local irritation. Do not inject into bruised, tender, lumpy, infected, or scarred skin. If redness spreads, pain worsens, or discharge appears at an injection site, contact a clinician.
Most compounded semaglutide vials should remain refrigerated at 2-8 C / 36-46 F and protected from light. When travelling, use an insulated medication bag with a cold pack, but keep the vial from direct contact with frozen packs so it does not freeze. Pack syringes and alcohol swabs separately and keep the prescription label with the vial where possible.
Some formulations may tolerate limited room-temperature storage, sometimes up to 30 days, but this is product-specific. Follow the pharmacy label first. If the vial has been left hot, frozen, cloudy, or exposed beyond the pharmacy's stated limit, ask the pharmacy before using it.
The dose escalation schedule in this guide reflects the protocol studied in the STEP 1 trial (semaglutide 2.4 mg/week for weight management in adults with obesity). The SELECT trial demonstrated cardiovascular risk reduction with semaglutide in adults with obesity or overweight without diabetes. Compounded semaglutide preparations are not covered by these trials — they used the branded formulation Wegovy. Always follow your prescriber's specific escalation schedule.
Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med. 2021;384:989–1002. · Lincoff AM, et al. Semaglutide and Cardiovascular Outcomes in Obesity without Diabetes. N Engl J Med. 2023;389:2221–2232.