Two vials labelled semaglutide can contain different concentrations, hold different volumes, and require completely different syringe markings to deliver the same dose. This is the least-discussed and most consequential difference between compounded providers.
Key Takeaways
- Compounded injectable concentration is not standardized across the market — mg per mL varies by pharmacy.
- A dose in milligrams translates to a different volume at every different concentration.
- Insulin syringes are marked in units, not milligrams or millilitres, which introduces a conversion step.
- The FDA has reported adverse events involving dosing errors with compounded semaglutide, including unit-conversion mistakes.
- Switching providers mid-treatment is the highest-risk moment, because your old dosing habit may not transfer.
| What varies | Why it varies | What it means for you |
|---|---|---|
| Concentration (mg/mL) | Each compounding pharmacy sets its own formulation | The same dose is a different volume at different providers |
| Fill volume per vial | Determines how many doses a vial contains | Affects your true cost per dose and your reorder timing |
| Multi-dose versus single-dose | Formulation and preservative decisions | Multi-dose vials have a beyond-use date once punctured |
| Syringe supplied | Provider choice | Unit markings must match the instructions you were given |
| Added ingredients | Some formulations include B12, L-carnitine or similar | Changes the preparation; not present in approved products |
The arithmetic that causes errors
Suppose your prescription is 0.25 mg weekly. If your vial is 2.5 mg per mL, that is 0.1 mL. If your next provider supplies 5 mg per mL, the same 0.25 mg dose is 0.05 mL — half the volume for an identical dose.
Now add the syringe. Insulin syringes are marked in units, where 100 units equals 1 mL. Your 0.1 mL is 10 units on the syringe; your 0.05 mL is 5 units. The number you are told to draw is a property of the concentration, not of the drug or the dose.
This is why "draw 10 units" is dangerous advice from anyone other than the provider who supplied your specific vial, and why a peer's dosing instruction from a forum is not transferable information.
MadeMed (Injectable Semaglutide)
Injectable- Monthly and quarterly billing options
- L-carnitine included in the injectable formulation
- Membership program available for refill discounts
Compounded medications are not FDA-approved. The FDA does not review compounded drugs for safety, effectiveness, or quality before they are marketed. Compounded GLP-1 medications are prepared by state-licensed pharmacies and are not the same as FDA-approved brand products.
Yucca Health
Injectable only- Clear intro-versus-ongoing split published up front
- Free UPS 2-Day Air shipping
- Klarna, Affirm and Afterpay available on 6-month plans
Injectable only. Yucca's headline promo rate is tied to the 6-month new-patient plan — the month-to-month rate is substantially higher.
Compounded medications are not FDA-approved. The FDA does not review compounded drugs for safety, effectiveness, or quality before they are marketed. Compounded GLP-1 medications are prepared by state-licensed pharmacies and are not the same as FDA-approved brand products.
Why this is a known safety problem
The FDA has publicly reported adverse events associated with compounded semaglutide, including dosing errors. Unit-conversion mistakes and confusion arising from differing concentrations feature in that reporting. Approved products avoid this class of error by supplying pens with fixed, dialled doses — the patient never performs arithmetic.
A vial and a syringe move that arithmetic to your kitchen table. That is not an argument against compounded medication, but it is an argument for treating the instructions that came with your specific vial as the only instructions that apply to it.
Telos Rx (Tirzepatide)
Flat pricing by plan length- Price is flat regardless of dose tier once your plan is set
- 12-month plan carries the lowest monthly rate; 1-month is the highest
- Cancel anytime; FSA/HSA accepted
Telos publishes plan-length pricing rather than dose-tier pricing, so the number you see at signup depends on the commitment you choose, not the milligrams you take.
Compounded medications are not FDA-approved. The FDA does not review compounded drugs for safety, effectiveness, or quality before they are marketed. Compounded GLP-1 medications are prepared by state-licensed pharmacies and are not the same as FDA-approved brand products.
SHED
Multi-format- Carries brand-name options alongside compounded: Wegovy pen $199, oral Wegovy pill $149, Zepbound $349 plus a $99 membership
- 120-day results guarantee (terms updated June 10, 2026)
- Multi-month terms convert to a different ongoing rate — read the conversion language
Price-jump disclosure: SHED's tirzepatide pricing increases to $399/mo once you reach the 7.5 mg maintenance tier. Budget for the higher number, not the entry number.
Compounded medications are not FDA-approved. The FDA does not review compounded drugs for safety, effectiveness, or quality before they are marketed. Compounded GLP-1 medications are prepared by state-licensed pharmacies and are not the same as FDA-approved brand products.
The switching checklist
If you change providers, re-verify every one of these before your first dose from a new vial:
- The concentration in mg per mL, printed on the label
- The volume, in mL, corresponding to your prescribed dose at that concentration
- The unit marking on the syringe you were supplied, and whether it matches the syringe you used before
- The beyond-use date, and whether it changes once the vial is punctured
- Whether the formulation includes added ingredients your previous one did not
If any of this is unclear on the label or in the accompanying materials, contact the provider before dosing. This is exactly the situation in which asking a question is much cheaper than guessing.
Found Health
4-week billing cycle- Bills in 4-week cycles, not calendar months — 13 cycles a year, not 12
- Behavior-change coaching bundled with the medication track
- Dissolvable tablet format
A 4-week cycle means your true annual cost is 13 × the quoted price. Worth doing the multiplication before comparing against a monthly-billed competitor.
Compounded medications are not FDA-approved. The FDA does not review compounded drugs for safety, effectiveness, or quality before they are marketed. Compounded GLP-1 medications are prepared by state-licensed pharmacies and are not the same as FDA-approved brand products.
Wellorithm
Lowest published oral price- Compounded tablet format — no needles, no cold chain
- Publishes per-format pricing rather than bundling everything into one plan
- Injectable options also offered
Compounded medications are not FDA-approved. The FDA does not review compounded drugs for safety, effectiveness, or quality before they are marketed. Compounded GLP-1 medications are prepared by state-licensed pharmacies and are not the same as FDA-approved brand products.
Frequently Asked Questions
Why do concentrations differ between providers?
Each compounding pharmacy sets its own formulation. There is no market-wide standard concentration for compounded semaglutide or tirzepatide.
Can you use the same syringe markings at a new provider?
Not safely. The unit number you draw depends on the concentration of the vial in front of you. Re-verify with every new supply.
What does beyond-use date mean?
It is the date after which a compounded preparation should not be used, assigned by the compounding pharmacy. For multi-dose vials it may be shorter once the vial is first punctured.
Are added ingredients like B12 a problem?
They are a difference from the approved products, and they mean the preparation you receive is not identical to what was studied in the registration trials. Whether they are appropriate for you is a question for your prescriber.