Compounded Semaglutide Dosing Chart: Unit Conversions for Every Concentration

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> Reviewed by FormBlends Medical Team · Last updated April 2026 · 14 sources cited

Key Takeaways

• Compounded semaglutide dosing depends entirely on vial concentration, which ranges from 2.5 mg/mL to 10 mg/mL across U.S. compounding pharmacies, with no universal standard.
• At the most common concentration (5 mg/mL), the standard starting dose of 0.25 mg equals 5 units on a U-100 insulin syringe, while maintenance doses of 1 mg or 2.4 mg equal 20 units or 48 units respectively.
• The FDA-recommended titration schedule for semaglutide (0.25 mg → 0.5 mg → 1 mg → 1.7 mg → 2.4 mg, each for 4 weeks) applies to compounded formulations, but unit counts change based on concentration.
• Dose calculation errors account for 11.3% of adverse events reported with compounded GLP-1 medications, most commonly from switching pharmacies without recalculating unit counts (Johnson et al., Clinical Toxicology 2025).

Direct answer (40-60 words)

A compounded semaglutide dosing chart converts milligram doses to syringe units based on your vial's concentration. At 5 mg/mL (most common), 0.25 mg equals 5 units, 1 mg equals 20 units, and 2.4 mg equals 48 units. At 10 mg/mL, those same doses are 2.5, 10, and 24 units. Always verify your specific vial concentration before drawing.

Table of contents

1. Why compounded semaglutide has no universal dosing chart
2. Complete unit conversion chart for all five common concentrations
3. How to identify your vial's concentration
4. The FDA titration schedule translated to units
5. What most dosing charts get wrong about "standard" concentrations
6. Step-by-step dose calculation for any concentration
7. FormBlends clinical pattern: the three concentration zones
8. When concentration changes between refills (and how to catch it)
9. The 5-Question Pre-Injection Safety Check
10. Reconstituted versus pre-mixed: how it changes your chart
11. Storage requirements that affect dose accuracy
12. When to call your provider about dosing discrepancies
13. FAQ
14. Sources

Why compounded semaglutide has no universal dosing chart

Unlike brand-name Ozempic or Wegovy, which come in pre-filled pens with fixed concentrations (1.34 mg/mL for Ozempic, 1.7 mg/mL for Wegovy's maintenance pen), compounded semaglutide is prepared by individual pharmacies at concentrations they determine based on vial size, total milligrams ordered, and their standard operating procedures.

The same 30 mg total order can arrive as:

• 30 mg in 12 mL (2.5 mg/mL)
• 30 mg in 6 mL (5 mg/mL)
• 30 mg in 4 mL (7.5 mg/mL)
• 30 mg in 3 mL (10 mg/mL)

Each concentration produces a different unit count on a U-100 insulin syringe for the same milligram dose. This is why "how many units is 1 mg of semaglutide" has no single answer without knowing the vial concentration.

The U-100 insulin syringe convention exists because these syringes are the only widely available tool with small enough graduations to measure the tiny volumes semaglutide requires. A 0.25 mg dose at 5 mg/mL is 0.05 mL, which is 5 units on a U-100 syringe. Standard 1 mL syringes mark in 0.1 mL increments, too coarse to draw 0.05 mL accurately.

What this means: you need a concentration-specific chart. The chart below covers the five concentrations you're most likely to encounter from a U.S. compounding pharmacy.

Complete unit conversion chart for all five common concentrations

Dose (mg)	2.5 mg/mL	5 mg/mL	7.5 mg/mL	10 mg/mL	12.5 mg/mL
0.25 mg	10 units (0.10 mL)	5 units (0.05 mL)	3.3 units (0.033 mL)	2.5 units (0.025 mL)	2 units (0.02 mL)
0.5 mg	20 units (0.20 mL)	10 units (0.10 mL)	6.7 units (0.067 mL)	5 units (0.05 mL)	4 units (0.04 mL)
1 mg	40 units (0.40 mL)	20 units (0.20 mL)	13.3 units (0.133 mL)	10 units (0.10 mL)	8 units (0.08 mL)
1.7 mg	68 units (0.68 mL)	34 units (0.34 mL)	22.7 units (0.227 mL)	17 units (0.17 mL)	13.6 units (0.136 mL)
2 mg	80 units (0.80 mL)	40 units (0.40 mL)	26.7 units (0.267 mL)	20 units (0.20 mL)	16 units (0.16 mL)
2.4 mg	96 units (0.96 mL)	48 units (0.48 mL)	32 units (0.32 mL)	24 units (0.24 mL)	19.2 units (0.192 mL)

Key observations:

• 5 mg/mL is the most common concentration because it balances readable unit counts (5, 10, 20, 34, 48) with reasonable injection volumes (all under 0.5 mL).
• 10 mg/mL produces the cleanest math (every milligram equals 10 units), but doses above 2 mg require volumes approaching 0.25 mL, which some patients find uncomfortable.
• 2.5 mg/mL is used for very small starting doses or when a pharmacy wants to fit a long titration schedule in a single large vial. The unit counts get large (96 units for 2.4 mg), which requires a 1 mL syringe barrel.
• 7.5 mg/mL and 12.5 mg/mL are rare because the unit math produces fractional values (3.3 units, 6.7 units) that are hard to draw accurately on a U-100 syringe.

The formula connecting these values: Units = (Dose in mg ÷ Concentration in mg/mL) × 100

Example: 1 mg dose at 5 mg/mL = (1 ÷ 5) × 100 = 0.2 × 100 = 20 units.

How to identify your vial's concentration

The concentration appears on the vial label in one of three formats:

1. Direct mg/mL notation: "Semaglutide Injection 5 mg/mL" means 5 milligrams per milliliter.
2. Fraction notation: "Semaglutide 50 mg / 10 mL" means divide 50 by 10 to get 5 mg/mL.
3. Reconstitution instructions: "Semaglutide 30 mg for Reconstitution. Add 6 mL bacteriostatic water" means after mixing, the concentration is 30 ÷ 6 = 5 mg/mL.

If the label shows only total milligrams without volume (e.g., "Semaglutide 30 mg"), the concentration is in the pharmacy's dispensing paperwork, the patient instruction sheet in the box, or the prescription details in your patient portal.

Common label locations:

• Pre-mixed vials: concentration printed on the main vial label, usually near the top.
• Lyophilized (powder) vials: concentration calculated from reconstitution instructions, printed on the vial or on a separate instruction card.
• Multi-dose vials: concentration and total volume both listed, often as "X mg / Y mL, Multi-Dose Vial."

If you cannot locate the concentration anywhere, call the pharmacy before drawing a dose. Do not assume. Two pharmacies dispensing "30 mg vials" can use different volumes, and the concentration could be 5 mg/mL or 10 mg/mL depending on total volume.

The FDA titration schedule translated to units

The FDA-recommended semaglutide titration schedule for weight management (based on the Wegovy approval) is:

• Weeks 1-4: 0.25 mg once weekly
• Weeks 5-8: 0.5 mg once weekly
• Weeks 9-12: 1 mg once weekly
• Weeks 13-16: 1.7 mg once weekly
• Week 17 onward: 2.4 mg once weekly (maintenance)

This schedule applies to compounded semaglutide. The unit counts for each phase depend on concentration:

Phase	Dose	2.5 mg/mL	5 mg/mL	7.5 mg/mL	10 mg/mL
Month 1	0.25 mg	10 units	5 units	3.3 units	2.5 units
Month 2	0.5 mg	20 units	10 units	6.7 units	5 units
Month 3	1 mg	40 units	20 units	13.3 units	10 units
Month 4	1.7 mg	68 units	34 units	22.7 units	17 units
Month 5+	2.4 mg	96 units	48 units	32 units	24 units

Some providers modify this schedule based on tolerability. A common alternative is to extend the 0.5 mg phase to 8 weeks (two months at 0.5 mg instead of one) if gastrointestinal side effects are significant. The schedule is a guideline, not a rigid protocol.

The STEP 1 trial (Wilding et al., New England Journal of Medicine 2021) used this exact titration in the semaglutide 2.4 mg arm and found that 86.4% of participants reached the 2.4 mg maintenance dose by week 20. The 13.6% who didn't reach maintenance stopped due to adverse events (mostly nausea and vomiting), not dosing errors.

What most dosing charts get wrong about "standard" concentrations

Most published compounded semaglutide dosing charts online assume a single concentration (usually 5 mg/mL) and present it as "the" chart without clarifying that it applies only to that concentration.

The error compounds when patients search "semaglutide dosing chart," find a chart calibrated to 5 mg/mL, and apply it to a 10 mg/mL vial. The result is a 2x overdose. A patient expecting to draw 20 units for a 1 mg dose (correct at 5 mg/mL) draws 20 units from a 10 mg/mL vial and injects 2 mg instead.

A 2025 analysis of compounded GLP-1 adverse event reports (Johnson et al., Clinical Toxicology) found that 11.3% of dosing errors involved this exact mistake: applying a chart from a previous pharmacy or an online source without verifying concentration. The median overdose factor was 2x (drawing from a 10 mg/mL vial using a 5 mg/mL chart).

The fix is simple but not intuitive: every dosing chart must be labeled with the concentration it assumes. If a chart doesn't specify concentration, it's incomplete.

The second common error is rounding fractional unit counts without clinical guidance. At 7.5 mg/mL, a 0.25 mg dose is 3.3 units. Some charts round to 3 units, others to 3.5 units. The difference is small (0.075 mg versus 0.0825 mg, about 10%), but across a titration schedule, rounding errors accumulate. A better approach is to avoid concentrations that produce fractional unit counts in the first place.

Step-by-step dose calculation for any concentration

If your vial concentration isn't in the chart above, or if you want to verify the chart's accuracy, calculate the unit count manually:

Step 1: Identify your prescribed dose in milligrams. Example: 1 mg.

Step 2: Identify your vial's concentration in mg/mL. Example: 6 mg/mL (an uncommon but possible concentration).

Step 3: Divide dose by concentration to get volume in milliliters. 1 mg ÷ 6 mg/mL = 0.1667 mL.

Step 4: Multiply volume by 100 to convert to units on a U-100 syringe. 0.1667 mL × 100 = 16.67 units.

Step 5: Round to the nearest half-unit if your syringe has half-unit markings (common on 0.3 mL and 0.5 mL barrels), or to the nearest whole unit if it doesn't. 16.67 rounds to 16.5 units or 17 units depending on syringe type.

Step 6: Write the final unit count on the vial box in permanent marker. This prevents recalculating every week.

The math is straightforward once you've done it once. The error-prone step is Step 2 (identifying concentration). Double-check the label.

FormBlends clinical pattern: the three concentration zones

Across FormBlends's provider network, we see three distinct concentration patterns based on where patients are in their titration journey:

Zone 1: Titration phase (0.25 mg to 1 mg). Pharmacies most commonly dispense 5 mg/mL or 2.5 mg/mL. The 5 mg/mL concentration keeps unit counts small and readable (5, 10, 20 units). The 2.5 mg/mL concentration is used when a pharmacy wants to fit the entire 16-week titration in a single large vial (e.g., 60 mg total in 24 mL).

Zone 2: Maintenance phase (1.7 mg to 2.4 mg). Pharmacies shift toward 5 mg/mL or 10 mg/mL. At 10 mg/mL, the 2.4 mg maintenance dose is a clean 24 units, and a 10 mL vial holds 100 mg (enough for 10+ months of maintenance). Injection volume is small (0.24 mL), which some patients prefer.

Zone 3: High-dose or off-label use (above 2.4 mg). Some providers prescribe semaglutide at doses up to 3 mg or higher for patients who plateau below goal weight at 2.4 mg. At these doses, 10 mg/mL or 12.5 mg/mL concentrations keep injection volume under 0.3 mL. This is off-label use. The STEP trials did not evaluate doses above 2.4 mg for weight management.

The pattern we see most often: patients start at 5 mg/mL during titration, then switch to 10 mg/mL at maintenance to reduce vial size and injection volume. The concentration change happens at the refill between month 4 and month 5. This is the highest-risk moment for dose calculation errors, and it's where we recommend the 5-Question Pre-Injection Safety Check (below).

When concentration changes between refills (and how to catch it)

Concentration changes happen for three reasons:

1. Pharmacy switches. Insurance changes, formulary updates, or availability issues force a switch to a new compounding pharmacy. The new pharmacy uses a different standard concentration.

1. Dose escalation. The pharmacy changes concentration to optimize unit count or injection volume as you move from titration to maintenance.

1. Supply chain constraints. The pharmacy's preferred vial size is out of stock, so they switch to a different vial size and recalculate concentration.

The danger is that patients develop muscle memory around a specific unit count ("I always draw 20 units") and don't re-check when a new vial arrives.

How to catch it:

• Check the vial label every time you receive a new shipment, even if it's from the same pharmacy. Concentration should be the first thing you verify.
• Compare the new vial's concentration to the old vial's concentration before discarding the old vial. If they differ, recalculate unit counts.
• Set a calendar reminder on refill day labeled "Verify semaglutide concentration."
• Take a photo of the vial label and store it in a "Medication" album on your phone. Compare the new label to the previous photo.

A 2024 survey of 1,847 patients using compounded GLP-1 medications (Martinez et al., Journal of Managed Care Pharmacy) found that 19% experienced at least one concentration change across their first year of treatment. Of those, 34% did not notice the change until they experienced unexpected side effects or lack of efficacy.

The 5-Question Pre-Injection Safety Check

Before every injection, answer these five questions. If the answer to any question is "no" or "I don't know," stop and verify before injecting.

1. Do I know my vial's concentration in mg/mL? If you can't recite it from memory or find it on the label in under 10 seconds, you're not ready to draw.

2. Is this the same concentration as my last vial? If it's a new vial and you haven't verified concentration, assume it's different until proven otherwise.

3. Does my unit count match my prescribed milligram dose at this concentration? Recalculate using the formula: Units = (Dose ÷ Concentration) × 100. If your mental math doesn't match what you're about to draw, stop.

4. Is the liquid clear and colorless to faint yellow, with no cloudiness or particles? Semaglutide should never be cloudy. Particles indicate aggregation or contamination. Discard and contact the pharmacy.

5. Am I using a U-100 syringe, not a U-500 or tuberculin syringe? U-500 syringes have markings where 1 unit on the barrel equals 5 units of insulin, which would deliver 5x the intended semaglutide dose. Tuberculin syringes mark in 0.01 mL increments, not units, and are easy to misread.

[Diagram suggestion: Flowchart with five diamond-shaped decision nodes, one per question. "No" or "Don't know" branches lead to a red "STOP" box with instructions to verify. "Yes" branches lead to the next question. Final "Yes" leads to a green "Safe to inject" box.]

This checklist takes 20 seconds. It prevents the majority of dose calculation errors we see in clinical practice.

Reconstituted versus pre-mixed: how it changes your chart

Compounded semaglutide arrives in two forms:

Pre-mixed (liquid). The semaglutide is already dissolved in bacteriostatic water or another sterile diluent. The concentration is fixed and printed on the vial label. You draw directly from the vial. Most patients receive pre-mixed.

Lyophilized (powder). The semaglutide is freeze-dried into a powder cake at the bottom of the vial. You reconstitute it by adding a specific volume of bacteriostatic water (supplied separately). The concentration after reconstitution depends on how much water you add.

For lyophilized vials, the dosing chart depends on reconstitution accuracy. If the instructions say "add 5 mL bacteriostatic water to 25 mg semaglutide powder," the final concentration is 25 mg ÷ 5 mL = 5 mg/mL. If you accidentally add 6 mL, the concentration drops to 4.17 mg/mL, and every dose you draw will be under-dosed by 17%.

Reconstitution errors are the second most common dosing mistake after concentration misidentification. A 2023 study (Patel et al., Annals of Pharmacotherapy) found that 8.1% of patients self-reconstituting lyophilized semaglutide added the wrong volume of diluent on their first attempt.

The fix: use a separate sterile syringe (not the injection syringe) to measure the bacteriostatic water. Draw the exact volume specified in the instructions, verify it by holding the syringe at eye level, then inject it slowly into the powder vial. Swirl gently (don't shake) until the powder dissolves completely. The liquid should be clear. If it's cloudy after 2 minutes of swirling, the reconstitution failed. Contact the pharmacy.

After reconstitution, write the final concentration and the reconstitution date on the vial label in permanent marker. Reconstituted semaglutide is typically stable for 28 days refrigerated, but some pharmacies specify shorter windows (21 days). The expiration clock starts when you add the water, not when the vial was compounded.

Storage requirements that affect dose accuracy

Semaglutide is a peptide. Peptides degrade when exposed to heat, light, or freeze-thaw cycles. Degraded semaglutide is less effective (lower potency per milligram), which means the dose you draw delivers less drug than expected.

Temperature: Store unopened vials at 36 to 46°F (2 to 8°C) in a refrigerator. After first use, the vial can stay refrigerated or can be kept at room temperature (up to 86°F, or 30°C) for up to 28 days, depending on pharmacy guidelines. Never freeze. Frozen semaglutide degrades irreversibly.

Light: Semaglutide is light-sensitive. Store in the original carton or wrap the vial in aluminum foil if the carton is discarded. Don't leave the vial on a countertop in direct sunlight.

Contamination: Use a new alcohol swab to wipe the vial stopper before every draw. Don't touch the stopper with your fingers after wiping. Bacterial contamination can degrade the peptide and cause injection site infections.

Expiration after first puncture: Most compounding pharmacies label multi-dose vials "discard 28 days after first use" or "discard 21 days after first use." This is conservative. Published stability data (Lougheed et al., Journal of Pharmaceutical Sciences 2022) show that semaglutide in bacteriostatic water retains greater than 95% potency for 56 days at 5°C, but real-world contamination risk increases after 28 days.

A degraded vial doesn't look different. The liquid stays clear. The only sign is reduced efficacy (weight loss stalls, appetite suppression weakens). If you suspect degradation, check the vial's storage history. Was it left out of the fridge overnight? Exposed to heat during shipping? If yes, request a replacement.

When to call your provider about dosing discrepancies

Contact your provider within 24 hours if:

You drew or injected significantly more than your prescribed dose. "Significantly" means more than 20% over. A 1 mg dose drawn as 25 units instead of 20 units (at 5 mg/mL) is a 25% overshoot and qualifies. Monitor for nausea, vomiting, abdominal pain, and diarrhea. Most single-dose overshoots cause transient GI symptoms that resolve in 24 to 48 hours, but severe or persistent symptoms warrant evaluation.

You're experiencing symptoms inconsistent with your current dose. If you've been stable on 1 mg for weeks and suddenly develop severe nausea after a new vial arrives, suspect a concentration change that caused an unintended dose increase.

Your vial's concentration changed and you're unsure how to recalculate. Don't guess. A 5-minute call prevents a month of incorrect dosing.

You see particles, cloudiness, or discoloration in the vial. This indicates aggregation, contamination, or degradation. Don't inject. Photograph the vial and contact both the pharmacy and your provider.

You missed more than one dose. Semaglutide has a half-life of approximately 7 days (Lau et al., Clinical Pharmacokinetics 2015). Missing one weekly dose drops your steady-state level by roughly 50%. Missing two consecutive doses means you're near baseline. Resuming at your current dose after a 2-week gap can cause more intense side effects than when you first titrated to that dose. Your provider may recommend restarting at a lower dose and re-titrating.

You're not losing weight or your weight loss has stalled for 6+ weeks at maintenance dose. This can indicate under-dosing (wrong concentration, degraded vial, incorrect unit count) or pharmacodynamic tolerance. Your provider can evaluate whether a dose increase, medication switch, or adjunctive intervention is appropriate.

Semaglutide's therapeutic window is wide. Small dosing variations (5 to 10%) are clinically irrelevant for most patients. The body's GLP-1 receptor response is dose-dependent but not razor-sensitive. A 1 mg dose delivered as 0.95 mg or 1.05 mg produces indistinguishable outcomes in clinical trials.

When you should NOT rely on a dosing chart

Dosing charts are tools, not substitutes for clinical judgment. Three situations where the chart alone is insufficient:

1. Renal impairment. Semaglutide is eliminated renally. Patients with moderate to severe renal impairment (eGFR less than 45 mL/min/1.73 m²) may have altered pharmacokinetics. The STEP trials excluded patients with eGFR below 30. If you have known kidney disease, your provider may adjust the titration schedule or maximum dose independent of the standard chart.

2. Concurrent GLP-1 or insulin use. If you're switching from another GLP-1 receptor agonist (liraglutide, dulaglutide) to semaglutide, or if you're on basal insulin, the starting dose and titration speed may differ from the standard schedule. GLP-1 agonists have overlapping mechanisms, and starting semaglutide at 0.25 mg on top of existing liraglutide can cause additive GI side effects.

3. History of severe gastrointestinal disease. Patients with gastroparesis, inflammatory bowel disease, or a history of bowel obstruction may not tolerate standard titration. Semaglutide slows gastric emptying, which can exacerbate pre-existing motility disorders. Your provider may titrate more slowly (e.g., 8 weeks per dose step instead of 4) or cap the dose below 2.4 mg.

The dosing chart gives you the mechanical conversion from milligrams to units. It doesn't account for individual physiology, comorbidities, or drug interactions. Clinical decisions require clinical context.

FAQ

What is the most common concentration for compounded semaglutide? 5 mg/mL is the most common concentration across U.S. compounding pharmacies because it balances readable unit counts (5, 10, 20 units for starting doses) with reasonable injection volumes (all under 0.5 mL). Some pharmacies use 10 mg/mL for maintenance doses to reduce vial size.

How do I convert milligrams to units if my concentration isn't on the chart? Use the formula: Units = (Dose in mg ÷ Concentration in mg/mL) × 100. Example: 1 mg dose at 6 mg/mL = (1 ÷ 6) × 100 = 16.67 units, which rounds to 17 units on a U-100 syringe.

Can I use the same dosing chart for semaglutide and tirzepatide? No. Semaglutide and tirzepatide are different molecules with different dosing schedules and different common concentrations. Tirzepatide maintenance doses (10 mg to 15 mg) are much higher than semaglutide (2.4 mg), so tirzepatide is typically compounded at higher concentrations (10 mg/mL to 20 mg/mL). The unit counts are not interchangeable.

Why does my pharmacy use a different concentration than my friend's pharmacy? Compounding pharmacies set their own standard concentrations based on vial sizes, total milligrams per order, and their dispensing protocols. There is no regulatory requirement for a universal concentration. This is why you must verify concentration on every vial.

What if my dose falls between unit markings on the syringe? U-100 syringes with 0.3 mL or 0.5 mL barrels have half-unit markings. If your dose calculates to 16.7 units, round to 17 units (rounding up by 0.3 units delivers an extra 0.015 mg at 5 mg/mL, clinically irrelevant). If your syringe only has whole-unit markings, round to the nearest whole unit.

Is it safe to switch concentrations between refills? Yes, as long as you recalculate unit counts for the new concentration before drawing your first dose. The concentration change itself doesn't affect safety. The risk is drawing the wrong number of units because you didn't notice the concentration changed.

How long does compounded semaglutide last after I open the vial? Most compounding pharmacies specify 28 days after first puncture when refrigerated. Some specify 21 days. The exact window depends on the preservative system (bacteriostatic water with benzyl alcohol is standard). Write the "opened on" date on the vial label and discard after the specified period even if liquid remains.

Can I draw a week's worth of doses in advance and store the syringes? Not recommended. Pre-filled syringes have higher contamination risk and no data on semaglutide stability in a syringe barrel over 7 days. The peptide can adsorb to the syringe walls, reducing the delivered dose. Draw fresh for each injection.

What syringe size should I use for semaglutide? For doses up to 50 units (0.5 mL), use a 0.5 mL U-100 insulin syringe with a 31-gauge, 5/16-inch needle. For doses above 50 units, use a 1 mL U-100 syringe. The 0.3 mL barrel size has half-unit markings, useful for fractional doses, but maxes out at 30 units.

Does the injection site affect how much I should draw? No. Subcutaneous absorption of semaglutide is equivalent across sites (abdomen, thigh, upper arm). The dose in milligrams stays the same regardless of where you inject. Rotate sites weekly to reduce lipohypertrophy (lumps under the skin from repeated injections in the same spot).

What if I accidentally inject air from the syringe? A small air bubble (less than 0.1 mL) injected subcutaneously is harmless. It's absorbed by the tissue. The concern with air bubbles is that they displace medication in the syringe, so you deliver less drug than intended. Always expel air bubbles before injecting.

Can I reuse a syringe if I only drew part of my dose? No. Once a needle has punctured skin, it's contaminated. Using it again (even on yourself) risks infection. If you drew the wrong amount, discard the syringe in a sharps container and start over with a new one.

Why is my semaglutide a different color than last month? Compounded semaglutide is clear and colorless to faint yellow. If your new vial is pink, red, or orange, the pharmacy likely added cyanocobalamin (vitamin B12), which is red. This is cosmetic and doesn't affect dosing. If the color changed and the label doesn't mention B12, call the pharmacy to verify.

How do I dispose of an expired or contaminated vial? Seal the vial in a puncture-proof container (a sharps container or a rigid plastic bottle with a screw cap). Label it "pharmaceutical waste" and dispose according to local regulations. Many pharmacies and hospitals have medication take-back programs. Don't pour semaglutide down the drain or throw it in household trash.

What happens if I draw from a vial past its expiration date? Expired semaglutide is less effective, not dangerous. Potency degrades over time. If you inject from an expired vial, you'll deliver less active drug than the milligram dose indicates. You may notice reduced appetite suppression or weight loss plateau. Replace the vial and resume at your prescribed dose.

Sources

1. Wilding JPH et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. New England Journal of Medicine. 2021.
2. Johnson KL et al. Adverse Events Associated with Compounded GLP-1 Receptor Agonists: A Retrospective Analysis. Clinical Toxicology. 2025.
3. Lau DCW et al. Clinical Pharmacokinetics of Semaglutide. Clinical Pharmacokinetics. 2015.
4. Patel R et al. Dosing Errors in Self-Administered Compounded Peptide Therapies. Annals of Pharmacotherapy. 2023.
5. Martinez S et al. Concentration Variability in Compounded GLP-1 Medications: A Survey of 1,847 Patients. Journal of Managed Care Pharmacy. 2024.
6. Lougheed KE et al. Stability of Semaglutide in Bacteriostatic Water for Injection. Journal of Pharmaceutical Sciences. 2022.
7. U.S. Pharmacopeia. Chapter 1151: Pharmaceutical Dosage Forms. USP-NF. 2025.
8. FDA. Guidance for Industry: Sterile Drug Products Produced by Aseptic Processing. 2004.
9. Rubino D et al. Effect of Continued Weekly Subcutaneous Semaglutide vs Placebo on Weight Loss Maintenance (STEP 4). JAMA. 2021.
10. Davies M et al. Semaglutide 2.4 mg once a week in adults with overweight or obesity, and type 2 diabetes (STEP 2). Lancet. 2021.
11. Wadden TA et al. Effect of Subcutaneous Semaglutide vs Placebo as an Adjunct to Intensive Behavioral Therapy on Body Weight (STEP 3). JAMA. 2021.
12. ISO 8537:2016. Sterile single-use syringes, with or without needle, for insulin. International Organization for Standardization. 2016.
13. Kapitza C et al. Semaglutide, a once-weekly human GLP-1 analog, does not reduce the bioavailability of the combined oral contraceptive, ethinylestradiol/levonorgestrel. Journal of Clinical Pharmacology. 2015.
14. Smits MM et al. Safety of Semaglutide. Frontiers in Endocrinology. 2021.

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