How long do reconstituted peptide vials last?
About 28 days at 2-8 C for most strength peptides. IGF-1 LR3 and a few others are more sensitive (14-21 days). Storage temperature is the key variable.
Updated May 8, 2026 · 6 min read
About 28 days for most strength peptides stored at 2-8 degrees Celsius (refrigerator). That's the practical working number for BPC-157, TB-500, ipamorelin, CJC-1295, sermorelin, and MOTS-c. A handful of peptides are more sensitive — IGF-1 LR3 typically holds for 14-21 days, and some of the longer chains degrade faster than the standard 28-day window. The single biggest determinant of shelf life is storage temperature; reconstitution diluent (BAC water vs sterile water) and light exposure are secondary but real factors.
The reference table by peptide
| Peptide | Refrigerated shelf life (2-8 C) | Notes |
|---|---|---|
| BPC-157 | ~28 days | Robust; tolerates mild excursions |
| TB-500 | ~28 days | Stable at standard concentrations |
| Ipamorelin | ~28 days | Stable when not exposed to light/heat |
| CJC-1295 (no DAC) | ~28 days | Stable refrigerated |
| CJC-1295 with DAC | ~30+ days | DAC tag improves stability |
| Sermorelin | ~14-28 days | Variable — finish sooner if possible |
| Tesamorelin | ~14-28 days | Sensitive to light and warming |
| IGF-1 LR3 | ~14-21 days | More sensitive — track carefully |
| MOTS-c | ~28 days | Stable refrigerated |
| GHK-Cu | ~30+ days | Copper peptide, naturally stable |
These are conservative working numbers based on commonly cited stability data and manufacturer practice. Actual stability depends on diluent, storage conditions, and the specific synthesis quality of your vial. Treating 28 days as the default and shortening for known-sensitive peptides is the right operating principle.
What "lasts" actually means
A peptide vial doesn't expire like milk — it doesn't go from "perfect" to "useless" overnight. It degrades on a curve:
| Time after reconstitution | Approximate potency (typical peptide, refrigerated) |
|---|---|
| Day 0 | 100% |
| Day 7 | ~98% |
| Day 14 | ~95% |
| Day 21 | ~92% |
| Day 28 | ~88-90% |
| Day 35 | ~82-85% |
| Day 42 | ~75-80% |
The 28-day cutoff is a practical convention, not a sharp cliff. At day 35 you're probably still getting most of the dose; at day 60 you're likely getting a meaningfully reduced dose; at day 90 the answer is anyone's guess. The convention exists because it's a clean, easy number to track and gives a comfortable margin against accelerated degradation from any storage missteps.
Why diluent matters
The water you reconstitute with sets the upper limit on shelf life:
| Diluent | Preservative | Reconstituted shelf life |
|---|---|---|
| Bacteriostatic water | 0.9% benzyl alcohol | ~28 days at 2-8 C |
| Sterile water (no preservative) | None | 24 hours, then discard |
| Saline (0.9% NaCl) | None | 24 hours, then discard |
Sterile water and saline have no antimicrobial preservative. Even refrigerated, contaminating organisms can grow in the vial across days, and the 24-hour rule is a safety convention. For multi-dose strength peptide protocols, BAC water is the only practical choice. See BAC water vs sterile water.
What shortens the shelf life
| Factor | Effect on shelf life |
|---|---|
| Room-temperature storage | Cuts shelf life from ~28 days to ~7 days |
| Hot exposure (over 30 C) | Hours to days, not weeks |
| Light exposure (UV/sunlight) | Variable; significant for photo-sensitive peptides |
| Freeze-thaw | Can ruin the vial in a single cycle |
| Repeated needle insertions through stopper | Minor; each insertion risks tiny contamination |
| Cloudy or particulate vial | Already degraded — discard |
| Color change | Already degraded — discard |
The single biggest variable is temperature. A vial that lives in the back of a stable, properly cold fridge will hit its full 28 days. A vial that bounces between fridge and travel cooler, fridge door (which swings warm), and counter for sessions will degrade faster.
For more, see storage temperatures by peptide.
Visual signs of degradation
Trust your eyes for first-pass quality control:
| Sign | What it means |
|---|---|
| Clear, colorless solution | Normal — peptide is intact |
| Cloudy or hazy | Aggregation — peptide structure is breaking down; discard |
| Visible particulates or floaters | Aggregation or contamination; discard |
| Color change (yellow, brown) | Oxidation or breakdown; discard |
| Crystals at bottom | Precipitation; discard |
| Unusual smell | Contamination or breakdown; discard |
Peptide solutions should look like water — clear, colorless, no visible content. Anything else is a signal to discard.
How to label and track
A simple labeling system that prevents most stale-vial errors:
On the vial cap (Sharpie):
"BPC 5/2 — 4/15 → 5/13"
Translation: BPC-157, 5 mg vial, 2 mL water, reconstituted April 15, expires (28 days later) May 13.
Every reconstituted vial should have:
- Peptide name (or abbreviation)
- Reconstitution date
- Calculated discard date (28 days, or shorter for sensitive peptides)
- Vial size and water volume (for re-checking dose math)
A small dot of nail polish on the cap can encode "vial 1, 2, 3" if you have multiple in rotation.
Practical examples
A typical 6-week BPC-157 cycle at 250 mcg/day:
5 mg vial + 2 mL BAC water = 2.5 mg/mL
250 mcg/day = 0.25 mg/day
Vial total: 5 mg / 0.25 mg per day = 20 days of dosing per vial
20 days < 28-day shelf life ✓
Two 5 mg vials cover the full 6-week cycle. The math fits the shelf life. No problem.
A 12-week cycle at 250 mcg/day:
Two vials cover 40 days. The 6-week balance (about 42 more days) requires a third vial — reconstituted around day 40.
Plan: keep the third vial lyophilized in the fridge until day 38-40, then reconstitute and immediately switch.
Don't reconstitute all your vials at once and store reconstituted vials for months. Reconstitute as you need them, in sequence.
When in doubt
If you're past day 28, the vial looks visually fine, and you don't have time to get a fresh one — the practical reality is most users will continue using it for another week or two. The risk is reduced potency, not safety, if the vial has been properly refrigerated and shows no visual signs of degradation. The clean answer is "discard at 28 days." The pragmatic answer is "watch for visual signs and prefer a fresh vial when feasible."
For sensitive peptides (IGF-1 LR3 in particular), don't push the window. Track the date and discard at 14-21 days as the table indicates.