Brand-name pens hide the math — click, inject, done. Compounded GLP-1s hand you a vial, a box of syringes, and a label that assumes you can read it. Most dosing errors in the compounded world are label-reading errors. Ten minutes here immunizes you.
Key Takeaways
- The critical line is concentration (mg/mL) — your prescribed dose in mg must be converted through it to syringe units, every vial, every time.
- On a standard U-100 insulin syringe, 100 units = 1mL. Dose (mg) ÷ concentration (mg/mL) × 100 = units to draw.
- New vial ritual: check the concentration before the first draw — pharmacies and refills can change it, same dose, different volume.
- The beyond-use date (BUD) is a compounded product's expiration — respect it, and note any 'after opening' storage change.
The Anatomy of the Label
Legally required elements you should locate on every vial: your name; the drug name (e.g., semaglutide, sometimes with additives like B12 noted); the concentration in mg/mL; total volume; the prescriber; the dispensing pharmacy's name and address (your actual counterparty — worth knowing); directions; storage instructions; and the beyond-use date. If any of these are missing — especially your name or the pharmacy — you're not holding a legitimately dispensed product.
The Only Math You Need
Insulin syringes measure volume in units: 100 units = 1mL on standard U-100 syringes. The conversion:
Units to draw = (Dose in mg ÷ Concentration in mg/mL) × 100
| Prescribed dose | Vial concentration | You draw |
|---|---|---|
| 0.25 mg | 2.5 mg/mL | 10 units |
| 0.5 mg | 2.5 mg/mL | 20 units |
| 1.0 mg | 2.5 mg/mL | 40 units |
| 1.0 mg | 5 mg/mL | 20 units |
| 2.4 mg | 10 mg/mL | 24 units |
Read the table's third and fourth rows twice: the same dose is a different draw at a different concentration. That is the entire reason the new-vial ritual exists.
The New-Vial Ritual
Every new vial — refill, new pharmacy, new provider — before the first draw: (1) confirm the drug name; (2) read the concentration; (3) recompute your units; (4) if anything changed from last vial, confirm with the pharmacy or provider before injecting. Thirty seconds. Pharmacies do change concentrations between fills, and provider switches change pharmacies. This ritual is the firewall.
Beyond-Use Dates and Storage
Compounded sterile products carry a BUD rather than a manufacturer expiration — typically a matter of weeks to a few months from compounding. Note it when the vial arrives and make sure your fill will be used within it. Follow the label's storage line (refrigeration is typical; some labels define a limited room-temperature allowance) — and when in doubt, the pharmacy on that label is exactly who to call. It's what they're for.
Pharmacy Quality Upstream of the Label
Telos Rx — Semaglutide
Compounded semaglutide — from $49/mo on 12-month plans
Flat pricing regardless of dose, with month-to-month through annual commitment tiers.
Compounded medications are not FDA-approved.
Visit Telos Rx Paid linkMadeMed — Injectable Semaglutide
Injectable semaglutide
Telehealth intake with pharmacy-shipped injectable semaglutide.
Compounded medications are not FDA-approved.
Visit MadeMed Paid linkWellorithm
Oral tablets — sema $147/mo, tirz $249/mo
The lowest published oral compounded pricing we currently track.
Compounded medications are not FDA-approved.
Visit Wellorithm Paid linkThe label is the one document between the pharmacy's work and your syringe. Read it like it matters, because it's the only step of the chain that's entirely yours.
Affiliate disclosure: Links marked "Paid link" are affiliate links. We may earn a commission if you sign up through them, at no extra cost to you. This supports our independent research.
Compounded medication notice: Compounded medications are not FDA-approved. The FDA does not verify the safety, effectiveness, or quality of compounded drugs before they are marketed. Brand-name alternatives (Wegovy, Ozempic, Zepbound, Rybelsus) are FDA-approved.
Medical disclaimer: This article is for informational purposes only and is not medical advice. GLP-1 medications are prescription drugs. Always consult a licensed healthcare provider about diagnosis, treatment, dosing, and whether these medications are appropriate for you.