Guide
Storing peptides correctly
Peptides are temperature-, light-, and time-sensitive. Get these four rules right and you'll preserve nearly every peptide on the market.
Cold
Fridge or freezer always — never a hot drawer or windowsill.
Dark
UV breaks down peptide bonds. Keep in original box or foil.
Dry
Lyophilized vials must stay sealed until you add BAC water.
Dated
Write the reconstitution date on the vial. Most lose potency past 30 days.
| State | Location | Temperature | Shelf life | Notes |
|---|---|---|---|---|
| Lyophilized (sealed) | Freezer | −20 °C / −4 °F | Up to 24 months | Original packaging, kept dark |
| Lyophilized (sealed) | Fridge | 2–8 °C / 36–46 °F | 3–6 months | If freezer isn't available |
| Lyophilized (sealed) | Room temp | ≤ 25 °C / 77 °F | Days to weeks | Shipping only — refrigerate on arrival |
| Reconstituted | Fridge | 2–8 °C / 36–46 °F | 28–60 days* | Back of fridge, not the door |
| Reconstituted | Freezer | Not recommended | — | Freeze-thaw degrades most peptides |
* Varies by peptide — semaglutide and tirzepatide are typically stable 28–56 days reconstituted.
Travel
- • Use a small insulated pouch with a frozen gel pack — keep vials cold but not touching ice.
- • Flying? Carry-on only. Bring the original labeled box and a doctor's note if prescribed.
- • On arrival, refrigerate within 4–6 hours.
Signs a peptide has gone bad
- • Cloudiness, particles, or stringy fibers in the solution.
- • Yellowing or any color change from clear.
- • Strong odor, sting on injection, or unusual injection-site reaction.
When in doubt, discard. Peptides are expensive — a bad shot is more expensive.