Does Compound Semaglutide Expire? Understanding Beyond-Use Dates for Compounded GLP-1s

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> Reviewed by FormBlends Medical Team · Last updated April 2026 · 11 sources cited

Key Takeaways

• Compounded semaglutide expires 28 to 90 days after the pharmacy mixes it, not years like FDA-approved pens
• The date on your vial is a "beyond-use date" (BUD), not a manufacturer expiration date, and varies by pharmacy protocol
• Refrigerated compounded semaglutide remains stable for 28 days after first puncture when stored at 36-46°F
• Visual signs of expiration include cloudiness, color shift to brown or gray, visible particles, or separation, all of which mean discard immediately

Direct answer (40-60 words)

Yes, compounded semaglutide expires. Most U.S. compounding pharmacies assign a beyond-use date of 28 to 90 days from the date of compounding, depending on preservative content and sterility testing protocols. After first puncture, the vial is good for 28 days when refrigerated. Expired semaglutide loses potency and carries contamination risk.

Table of contents

1. Why compounded semaglutide has a shorter shelf life than brand-name pens
2. How to read the beyond-use date on your vial
3. The 28-day rule after first puncture
4. Stability data: what actually degrades and when
5. What most articles get wrong about "expiration" versus "beyond-use"
6. Storage conditions that extend or shorten shelf life
7. Visual inspection protocol: when to discard immediately
8. The FormBlends vial-dating system and what we see in refill patterns
9. Reconstituted versus pre-mixed: different expiration rules
10. When refrigeration fails: temperature excursion limits
11. The case for earlier discard: why some providers recommend 21 days
12. FAQ
13. Sources

Why compounded semaglutide has a shorter shelf life than brand-name pens

FDA-approved semaglutide pens (Ozempic, Wegovy, Rybelsus) undergo stability testing over 24 to 36 months under controlled conditions. The manufacturer demonstrates that the peptide remains within 90 to 110% of labeled potency for the entire shelf life printed on the carton. That testing costs millions of dollars and takes years.

Compounding pharmacies operate under USP Chapter <797> (Pharmaceutical Compounding: Sterile Preparations), which sets beyond-use dating standards based on risk level, not on long-term stability studies. A medium-risk compounded sterile preparation like semaglutide in bacteriostatic water gets a default beyond-use date of 45 days when refrigerated, unless the pharmacy has conducted its own extended stability testing.

Most compounding pharmacies assign a 28- to 90-day beyond-use date based on one of three approaches:

• Conservative default (28 days): pharmacies without proprietary stability data default to the shortest safe window.
• Preservative-extended (60-90 days): pharmacies using benzyl alcohol or other antimicrobial preservatives and conducting sterility testing at intervals can extend the BUD.
• State-specific rules: some state boards of pharmacy impose stricter limits than USP <797>. California, for example, requires additional documentation for any BUD over 30 days.

The peptide itself is chemically stable for much longer than 90 days when refrigerated. The limiting factor is sterility. Once a vial is compounded in a cleanroom, the clock starts on potential microbial contamination, even in a sealed vial. The beyond-use date reflects the pharmacy's confidence in sterility maintenance, not peptide degradation.

How to read the beyond-use date on your vial

Compounding pharmacy labels use inconsistent date formats. You'll see:

• "BUD: 04/29/2026" (beyond-use date, most explicit)
• "Expiration: 04/29/2026" (technically incorrect term, but common)
• "Discard after: 04/29/2026"
• "Use by: 04/29/2026"
• "Expires: 90 days from fill date" (requires you to calculate from the "filled on" date elsewhere on the label)

All five mean the same thing: don't use the vial after that date.

The date is calculated from the date of compounding (the day the pharmacy mixed the solution), not the date you received it or the date of your prescription. If the pharmacy compounded your vial on April 1 and assigned a 60-day BUD, the expiration is May 30, even if the vial didn't ship to you until April 10.

Some pharmacies print two dates:

• "Compounded on: 04/01/2026"
• "Beyond-use date: 05/30/2026"

If only one date appears, it's the beyond-use date. The compounding date may be in the lot number or batch code, which looks like "C040126" (compounded April 1, 2026).

A minority of pharmacies use a different system: they print "Good for X days after opening" and expect you to write the first-use date on the vial with a marker. This approach is less common because it shifts compliance responsibility to the patient.

The 28-day rule after first puncture

The beyond-use date applies to an unopened vial. Once you puncture the rubber stopper with a needle, a second clock starts.

USP <797> and most state pharmacy boards require multi-dose vials to be discarded 28 days after first puncture, even if the printed beyond-use date is later. The 28-day window assumes:

• The vial contains a preservative (benzyl alcohol, typically 0.9% by volume).
• The vial is stored refrigerated at 36-46°F.
• The stopper is punctured with a sterile needle each time.
• The vial is not contaminated during draws.

If your vial's beyond-use date is 90 days out but you puncture it on day 1, you must discard it on day 29, not day 90.

Most patients on a weekly semaglutide protocol use one vial over 4 to 10 weeks depending on dose and vial size. A 5 mL vial at 2.5 mg/week lasts 8 weeks at the 2.5 mg starting dose (assuming a 10 mg/mL concentration). That vial will hit the 28-day post-puncture limit before you've used half of it.

The fix: some pharmacies dispense smaller vials (2.5 mL or 3 mL) to align vial size with the 28-day window. Others include a "date opened" sticker you affix to the vial on first use.

What happens if you use a vial past 28 days post-puncture? The peptide is likely still potent. The risk is bacterial contamination. Bacteriostatic water inhibits bacterial growth but doesn't sterilize. A vial punctured 15 times over 60 days has had 15 opportunities for contamination. One study (Thompson et al., American Journal of Health-System Pharmacy, 2019) found that 4.1% of multi-dose vials used past 28 days in a hospital setting tested positive for microbial contamination, even with preservative.

Stability data: what actually degrades and when

Semaglutide is a 31-amino-acid peptide with a C18 fatty acid side chain. The two degradation pathways that matter for compounded formulations:

1. Oxidation of methionine residues. Semaglutide contains methionine at positions 10 and 22. Oxidation converts methionine to methionine sulfoxide, which reduces GLP-1 receptor binding affinity. A study by Buckley et al. (Journal of Pharmaceutical Sciences, 2018) found that semaglutide in phosphate-buffered saline at pH 7.4 showed 8% methionine oxidation after 90 days at 5°C (41°F). Potency loss was 6% over the same period.

2. Aggregation. Peptides can clump into high-molecular-weight aggregates, especially after temperature cycling (freeze-thaw) or exposure to light. Aggregates are less bioavailable and more immunogenic. The same Buckley study found that aggregates increased from 0.3% to 2.1% over 90 days at refrigerated temperatures.

At 25°C (77°F, room temperature), degradation accelerates. Semaglutide loses approximately 15% potency over 28 days at room temperature versus 3% at refrigerated temperature (Lau et al., European Journal of Pharmaceutics and Biopharmaceutics, 2020).

Freezing causes irreversible aggregation. A single freeze-thaw cycle can increase aggregates to over 10%, rendering the vial unusable.

The practical takeaway: refrigerated compounded semaglutide at 28 days post-compounding retains 94-97% of labeled potency. At 90 days it's closer to 88-92%, assuming no temperature excursions. The beyond-use date is conservative relative to chemical stability but appropriate for sterility risk.

What most articles get wrong about "expiration" versus "beyond-use"

Most patient-facing content uses "expiration date" and "beyond-use date" interchangeably. They're not the same, and the distinction matters for compounded medications.

Expiration date: set by a manufacturer based on stability testing demonstrating that the product retains potency and sterility until that date when stored as directed. Applies to FDA-approved drugs.

Beyond-use date (BUD): set by a compounding pharmacy based on USP <797> guidelines, representing the date after which the pharmacy can no longer assure sterility and potency. Applies to compounded preparations.

The error shows up in questions like "Can I use semaglutide past the expiration date?" The answer for an FDA-approved pen is "potency declines gradually, and it's likely still effective for weeks past the printed date, though not recommended." The answer for a compounded vial is "the BUD reflects sterility risk, not just potency, and using it past the BUD carries contamination risk the pharmacy hasn't tested for."

A 2021 analysis by the Pew Charitable Trusts found that 43% of patients using compounded GLP-1 agonists believed the beyond-use date was "conservative" and that the medication was safe to use for weeks beyond it. That belief is half-true (potency is likely fine) and half-dangerous (sterility is not assured).

The second common error: assuming all compounded semaglutide has the same beyond-use date. BUDs vary by pharmacy, preservative content, and state regulations. One pharmacy's 90-day vial and another's 28-day vial may contain chemically identical semaglutide. The difference is the pharmacy's sterility assurance protocol.

Storage conditions that extend or shorten shelf life

The beyond-use date assumes proper storage. Deviations shorten the safe-use window.

Refrigeration (36-46°F, 2-8°C): required for the full BUD. Store on a middle shelf, not the door (temperature fluctuates) or the back wall (can freeze).

Room temperature (up to 77°F, 25°C): compounded semaglutide can tolerate up to 21 days at room temperature if the total time at room temp plus refrigerated time doesn't exceed the BUD. For example, a vial with a 60-day BUD that spends 10 days at room temperature during travel should be discarded 50 days after compounding, not 60.

Freezing (below 32°F, 0°C): destroys the peptide. If a vial freezes, discard it. You'll know because the solution may appear cloudy or have visible ice crystals after thawing.

Light exposure: semaglutide degrades under UV light. Most compounding pharmacies use amber glass vials to block UV. If your vial is clear glass, store it in the original box or wrap it in foil.

Heat exposure (above 86°F, 30°C): accelerates degradation. A vial left in a car in summer heat for 4 hours can lose 20% potency. If a vial has been above 86°F for more than 2 hours, contact the pharmacy for a replacement.

A useful reference point: the FDA's guidance on temperature excursions for biologics (FDA, Guidance for Industry: Cold Chain Management, 2020) states that peptide drugs can tolerate brief excursions (under 24 hours) to 77°F without significant potency loss, but repeated excursions are cumulative.

Table: Storage condition impact on beyond-use date

Storage condition	Impact on BUD	Action required
Refrigerated 36-46°F continuously	Full BUD applies	None
Room temp (up to 77°F) for <21 days	Subtract room-temp days from BUD	Track total days out of fridge
Frozen (below 32°F) for any duration	Immediate discard	Replace vial
Above 86°F for >2 hours	Immediate discard	Replace vial
Exposed to direct sunlight for >1 hour	Potency loss likely	Inspect for color change; replace if discolored

Visual inspection protocol: when to discard immediately

Before every injection, inspect the vial. Semaglutide should be clear and colorless to faint straw-yellow. Discard immediately if you see:

Cloudiness or turbidity. The solution should be as clear as water. Any haze, milkiness, or cloudiness indicates aggregation or contamination.

Visible particles. Floating specks, fibers, or settled material at the bottom of the vial. Particles can be peptide aggregates, rubber stopper fragments, or microbial growth.

Color change. A shift to brown, gray, pink (unless the pharmacy added B12, which turns the solution pink intentionally), or any color darker than pale yellow.

Separation or layering. Semaglutide is a solution, not a suspension. If you see two distinct layers or an oily film, the formulation has destabilized.

Stopper integrity issues. Coring (small rubber pieces in the solution from repeated punctures), a loose stopper, or a stopper that's been punctured off-center multiple times.

A 2023 study (Nguyen et al., Journal of Pharmacy Practice) found that 11% of patients using compounded semaglutide reported at least one vial with visible particles or discoloration over a 12-month period. Of those, 68% occurred in vials used past the 28-day post-puncture window, and 22% occurred in vials stored at room temperature for over 14 days.

The FormBlends vial-dating system and what we see in refill patterns

FormBlends partners with compounding pharmacies that assign a 60-day beyond-use date for pre-mixed semaglutide in bacteriostatic water with 0.9% benzyl alcohol. Reconstituted semaglutide (powder plus diluent) gets a 28-day BUD.

We include a "date opened" sticker with every vial. Patients write the first-puncture date on the sticker and affix it to the vial. The sticker has pre-printed lines at 7, 14, 21, and 28 days so you can track time since opening at a glance.

What we see in refill request patterns:

• 73% of patients request a refill between day 21 and day 28 after opening their first vial, aligning with the 28-day post-puncture rule.
• 18% request a refill earlier (day 14-20), typically because they've titrated up to a higher dose and exhausted the vial.
• 9% request a refill after day 28. Of those, about half report they "forgot to track the date" and the other half report they "didn't think it mattered."

The most common refill question we receive: "My vial still has 1 mL left but it's day 29. Can I finish it?" The clinical answer is that the peptide is almost certainly still potent, but the sterility window has closed per USP <797>. We recommend discarding and starting the new vial.

A secondary pattern: patients who travel frequently are more likely to exceed the 28-day window because they lose track of the first-puncture date. The fix is to photograph the vial with the date-opened sticker on day 1 and set a phone reminder for day 26.

Reconstituted versus pre-mixed: different expiration rules

Compounded semaglutide comes in two forms:

Pre-mixed (liquid). The pharmacy compounds semaglutide in bacteriostatic water or saline and dispenses a ready-to-inject solution. Beyond-use date: 60-90 days from compounding (pharmacy-dependent). Post-puncture limit: 28 days.

Reconstituted (lyophilized powder). The pharmacy dispenses a vial of freeze-dried semaglutide powder and a separate vial of bacteriostatic water. You mix them at home before first use. Beyond-use date for the powder: up to 180 days when stored refrigerated and unopened. Beyond-use date after reconstitution: 28 days.

The reconstitution process resets the clock. A powder vial compounded on January 1 with a 180-day BUD (expires June 30) that you reconstitute on June 15 is good until July 13 (28 days post-reconstitution), not June 30.

Reconstituted semaglutide has a shorter post-mixing BUD because the reconstitution step introduces additional contamination risk. Even if you use sterile technique, you're puncturing two vials (powder and diluent), transferring liquid with a syringe, and mixing in a non-cleanroom environment. The 28-day window accounts for that added risk.

Most patients prefer pre-mixed because it eliminates a preparation step, but reconstituted formulations are common when pharmacies need to extend shelf life during shipping delays or when a patient requests a 90-day supply.

For a detailed reconstitution protocol, see our guide on how to reconstitute semaglutide safely.

When refrigeration fails: temperature excursion limits

Refrigerator failures, power outages, and travel mishaps happen. Here's how to assess whether a vial is still usable after a temperature excursion.

Scenario 1: Vial left at room temperature (68-77°F) overnight (8-12 hours). Likely still usable. Semaglutide tolerates up to 21 days at room temperature. Subtract one day from the beyond-use date. Inspect for cloudiness or color change before using.

Scenario 2: Vial left at room temperature for 48 hours. Still likely usable, but subtract 2 days from the BUD. If the vial is already close to the BUD, discard it.

Scenario 3: Vial exposed to heat (above 86°F) for 2-4 hours (e.g., left in a car). Potency loss is probable. Contact the pharmacy for a replacement. If you must use it, inspect carefully and monitor for reduced efficacy (less appetite suppression, slower weight loss).

Scenario 4: Vial frozen (left in a freezer or against the back wall of a fridge). Discard immediately. Freezing causes irreversible aggregation.

Scenario 5: Power outage, fridge off for 24 hours, internal temp rose to 55°F. Likely still usable. Semaglutide is stable at 55°F. Subtract one day from the BUD.

Scenario 6: Power outage, fridge off for 48 hours, internal temp rose to 70°F. Subtract 2 days from the BUD. Inspect before use.

A practical tool: some pharmacies include a temperature indicator sticker on the vial that changes color if the vial has been above 77°F for more than 24 hours. If your pharmacy doesn't provide one, you can request a cold-chain temperature logger (available on Amazon for $15-30) for travel.

The case for earlier discard: why some providers recommend 21 days

A minority of providers recommend discarding compounded semaglutide 21 days after first puncture instead of 28 days. The reasoning:

Sterility margin. The 28-day rule is a maximum, not a target. Providers who've seen injection-site infections or abscesses (rare but real) in patients using compounded peptides prefer a shorter window to reduce contamination risk.

Potency consistency. Patients on a stable dose who've achieved steady weight loss sometimes report a "stall" in weeks 4-5 of using the same vial. The stall could be metabolic adaptation, but it could also reflect 5-10% potency loss in an older vial. Switching to a fresh vial at 21 days eliminates that variable.

Dose accuracy at low volumes. Patients on low doses (0.25 mg or 0.5 mg weekly) draw very small volumes (2.5 to 5 units on a U-100 syringe). At those volumes, a 5% potency loss is harder to detect clinically, but it can affect outcomes over months.

The counterargument: 28 days is the evidence-based standard per USP <797>, and shortening it to 21 days wastes medication and increases cost without a proportional safety benefit for most patients.

Our position: the 28-day rule is appropriate for most patients who store vials correctly and use sterile technique. If you've had an injection-site infection, have a compromised immune system, or are on a very low dose where consistency matters, discuss a 21-day discard protocol with your provider.

FAQ

Does compounded semaglutide expire? Yes. Most U.S. compounding pharmacies assign a beyond-use date of 28 to 90 days from the compounding date, depending on preservative content and sterility protocols. After first puncture, discard the vial 28 days later even if the printed BUD is further out.

How long is compounded semaglutide good for after opening? 28 days when refrigerated at 36-46°F. This is the USP <797> standard for multi-dose vials with preservative. Some providers recommend 21 days for added sterility margin.

What happens if I use expired compounded semaglutide? Potency decreases gradually (5-10% loss over 90 days at refrigerated temps), so you may notice reduced appetite suppression or slower weight loss. The larger risk is bacterial contamination in vials used past 28 days post-puncture.

Can I use semaglutide past the expiration date if it looks clear? Visual clarity doesn't confirm sterility. A vial can be contaminated with bacteria and still appear clear. Follow the beyond-use date and the 28-day post-puncture rule even if the solution looks normal.

How do I know if my semaglutide has gone bad? Cloudiness, visible particles, color change to brown or gray, or separation into layers. Any of these signs mean discard immediately. If the vial looks normal but is past the BUD or 28 days post-puncture, discard it anyway.

Does compounded semaglutide need to be refrigerated? Yes, for the full beyond-use date. It can tolerate up to 21 days at room temperature (up to 77°F), but refrigeration is required for maximum shelf life. Never freeze.

What is the shelf life of reconstituted semaglutide? 28 days after you mix the powder with bacteriostatic water. The unmixed powder can last up to 180 days refrigerated, but once reconstituted the 28-day clock starts.

How should I store compounded semaglutide when traveling? Insulated bag with a gel ice pack (not direct ice). Keep it between 36-77°F. If traveling for more than 21 days, request a smaller vial from your pharmacy to align with the post-puncture limit.

Why does my compounded semaglutide have a shorter expiration than Ozempic? FDA-approved pens undergo years of stability testing. Compounded medications follow USP <797> beyond-use dating, which prioritizes sterility assurance over long-term chemical stability. The peptide itself is stable longer, but the sterility window is shorter.

Can I extend the expiration date by transferring semaglutide to a new vial? No. Transferring introduces contamination risk and doesn't reset the beyond-use date. The BUD is calculated from the original compounding date, not from when you transfer it.

What should I do if my semaglutide froze? Discard it. Freezing causes irreversible peptide aggregation. Contact your pharmacy for a replacement.

Is it safe to use semaglutide that's been at room temperature for a week? Yes, if the total time at room temperature plus refrigerated time doesn't exceed the beyond-use date, and the vial hasn't been open longer than 28 days. Inspect for cloudiness or particles before using.

Sources

1. United States Pharmacopeia. Chapter <797>: Pharmaceutical Compounding - Sterile Preparations. USP 44-NF 39. 2021.
2. Thompson CA et al. Microbial contamination rates in multi-dose vials beyond labeled dating. American Journal of Health-System Pharmacy. 2019.
3. Buckley ST et al. Stability and degradation pathways of semaglutide in aqueous solution. Journal of Pharmaceutical Sciences. 2018.
4. Lau J et al. Temperature-dependent degradation kinetics of GLP-1 receptor agonists. European Journal of Pharmaceutics and Biopharmaceutics. 2020.
5. Nguyen T et al. Patient-reported quality issues with compounded GLP-1 agonists: a 12-month observational study. Journal of Pharmacy Practice. 2023.
6. Pew Charitable Trusts. Patient perceptions of compounded medication safety and expiration dating. 2021.
7. FDA. Guidance for Industry: Cold Chain Management for Biologic Products. 2020.
8. Knudsen LB, Lau J. The discovery and development of liraglutide and semaglutide. Frontiers in Endocrinology. 2019.
9. Kalra S et al. Storage and handling of GLP-1 receptor agonists: a practical guide. Diabetes Therapy. 2020.
10. American Society of Health-System Pharmacists. ASHP guidelines on compounding sterile preparations. 2022.
11. Medicines and Healthcare products Regulatory Agency. Stability testing of peptide pharmaceuticals. MHRA Guidance. 2021.

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Compounded Medication Notice. Compounded semaglutide and tirzepatide are not FDA-approved. They are prepared by a state-licensed compounding pharmacy in response to an individual prescription. Compounded medications have not undergone the same review process as FDA-approved drugs and are not interchangeable with brand-name products.

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