Why is there no single semaglutide + B12 dosage chart?
Unlike FDA-approved branded drugs, which have fixed, published dosage schedules, compounded semaglutide is prepared on a patient-specific basis by licensed 503A compounding pharmacies. Each pharmacy may formulate the product somewhat differently — including the amount of methylcobalamin (B12) added — and prescribers may specify dosing based on individual clinical factors.
That is why you will find inconsistency across forums, telehealth platforms, and pharmacy websites. One source may list 0.5 mg of B12 per injection; another may list 1 mg. Both can be correct — they are just different formulations from different pharmacies, or different prescriber specifications.
The only dosage chart that matters for your situation is the one on your dispensing label or in your prescriber’s notes. This article explains the general principles so you can interpret that information intelligently.
What does a typical semaglutide dose-escalation schedule look like?
The semaglutide component of a compounded formulation typically follows an escalation schedule derived from the branded STEP trial protocols, adapted by the prescribing clinician for the individual patient. A common schedule:
| Weeks | Semaglutide dose (typical) | B12 component |
|---|---|---|
| Weeks 1–4 | 0.25 mg weekly | Per pharmacy/prescriber specification |
| Weeks 5–8 | 0.5 mg weekly | Per pharmacy/prescriber specification |
| Weeks 9–12 | 1.0 mg weekly | Per pharmacy/prescriber specification |
| Weeks 13–16 | 1.7 mg weekly (if indicated) | Per pharmacy/prescriber specification |
| Week 17+ | 2.4 mg weekly (maintenance) | Per pharmacy/prescriber specification |
Note: This table reflects a common clinical pattern, not a universal protocol. Compounded semaglutide is not an FDA-approved drug, and no compounded formulation is equivalent to branded Ozempic or Wegovy. Your prescribing clinician sets your actual schedule.
How is the B12 dose typically structured?
In most compounded semaglutide formulations, the methylcobalamin dose is consistent across the titration schedule even as the semaglutide dose escalates. This reflects the clinical logic: the B12 supplementation is addressing a nutritional support need that exists throughout the protocol, not a dose-dependent interaction with semaglutide.
Methylcobalamin doses in compounded semaglutide range widely across pharmacies:
- 500 mcg (0.5 mg) per injection — common in lower-B12 formulations, particularly for patients with no identified deficiency risk.
- 1,000 mcg (1 mg) per injection — the more common range in telehealth-adjacent compounding; reflects a more conservative supplementation approach for patients on a reduced-calorie protocol.
- Higher doses — occasionally specified for patients with documented low B12 levels, metformin co-use, or other factors that increase depletion risk. These are clinician-directed.
B12 is water-soluble. Excess is excreted renally. There is no established toxicity threshold at doses typical of supplementation. However, clinical decisions about supplemental dose should still rest with your prescribing clinician, not a population-average table.
The only B12 dosage chart that governs your injection is the one printed on your dispensing label — not a number copied from a forum.
Why do prescribers include B12 in a semaglutide formulation?
The clinical rationale for adding methylcobalamin to a semaglutide injection:
- Appetite suppression reduces dietary B12 intake. Semaglutide significantly reduces caloric intake. Patients eating considerably less than their baseline diet consume less dietary B12 — particularly if their protein sources (meat, fish, eggs) are reduced as part of the dietary shift.
- Injection bypasses GI absorption variability. Subcutaneous injection delivers B12 directly for systemic absorption without relying on intrinsic factor in the gut.
- Patient convenience. One injection per week rather than an injection plus daily oral supplementation improves adherence.
- Metformin co-use. Metformin is associated with B12 depletion over time. Patients co-prescribed metformin with semaglutide benefit from proactive B12 support.
What should you check on your formulation label?
When you receive compounded semaglutide from a licensed 503A pharmacy, your dispensing label should specify:
- The concentration of semaglutide per mL
- The concentration of methylcobalamin (or B12) per mL
- The prescribed injection volume at each dose level
- The pharmacy name, license number, and compounding date
If your label does not clearly specify the B12 component and its concentration, that is a reasonable question to ask your pharmacy directly before injecting. A legitimate 503A pharmacy will provide full formulation transparency.
Frequently asked questions
How much B12 is in a typical semaglutide + B12 compounded injection?
There is no single standardized dose — each compounding pharmacy formulates the B12 component differently, and prescribers may specify a dose. Common ranges in compounded semaglutide formulations run from 0.5 mg to 1 mg (500–1,000 mcg) of methylcobalamin per weekly injection, but this varies. Your pharmacy dispensing label and your prescribing clinician are the authoritative sources for your specific formulation.
Does the B12 dose in semaglutide change as the semaglutide dose goes up?
In many compounded formulations, the methylcobalamin amount is fixed while the semaglutide dose escalates across the titration schedule. Some pharmacies adjust the B12 proportionally; others hold it constant. This is a formulation decision made by the compounding pharmacy and your prescriber — not a standard enforced across the industry.
Is methylcobalamin or cyanocobalamin used in semaglutide compounding?
Most compounded semaglutide formulations from licensed 503A pharmacies use methylcobalamin — the biologically active, methylated form of B12. Cyanocobalamin is less common in this context because methylcobalamin does not require hepatic conversion, making it preferable for injection delivery.
Can I request semaglutide without B12 added?
Yes, in principle. 503A compounding pharmacies prepare patient-specific formulations based on the prescriber's order. If you have a clinical reason to avoid B12 (for example, a confirmed methylation issue or a specific dietary supplementation plan), discuss this with your prescribing clinician. The clinician can specify a B12-free formulation.
Does more B12 in the injection produce better results?
B12 is water-soluble and excess amounts are excreted renally, so higher doses do not accumulate harmfully at typical supplemental ranges. However, there is no evidence that higher B12 dosing enhances semaglutide's weight management effect. The B12 component addresses nutritional support — it is not a performance enhancer for the GLP-1 mechanism.