Storage at a glance
| State | Where | How long |
|---|---|---|
| Lyophilized, unopened | Freezer, minus 20 °C | Longest life, up to the expiry on the label |
| Lyophilized, unopened | Fridge, 2 to 8 °C | Suitable for use within a few weeks |
| Reconstituted with bacteriostatic water | Fridge, 2 to 8 °C | Use within about 28 days |
| Bacteriostatic water, unopened | Room temperature | Up to the expiry on the label |
Before mixing
Unopened lyophilized vials keep longest in a freezer at minus 20 °C. For use within a few weeks, a fridge at 2 to 8 °C is fine. Keep vials in their carton, because light degrades many peptides.
Before opening a cold vial, let it reach room temperature so moisture does not condense inside.
After mixing
Once reconstituted with bacteriostatic water, keep the vial refrigerated and plan to use it within 28 days, the standard use window for a punctured multi-dose vial. Avoid freezing and thawing a mixed vial repeatedly, because each cycle can degrade the peptide.
This is why vial size matters: choose a size you will use inside that window. For example, retatrutide comes in 10, 20 and 30 mg vials for this reason.
When your order arrives
Orders ship by standard or express post. When your parcel arrives, move the vials to the fridge or freezer straight away. Lyophilized powder tolerates normal transit well; it is the reconstituted solution that needs constant refrigeration.
Signs a vial should not be used
- The solution is cloudy or has particles after reconstitution.
- The powder cake has turned sticky, discoloured or has collapsed into a gel (GHK-Cu is blue, which is normal).
- The vial seal or stopper is damaged.
- It has passed its expiry, or the 28 day window after mixing.
