Short answer: Not mixed or liquid products, per every label we checked: Ozempic, Wegovy, Mounjaro, Zepbound, Saxenda, Victoza, Norditropin, Genotropin, Humatrope, Omnitrope, Pregnyl and Egrifta all say do not freeze, and several say do not use if it has been frozen. Freezing stresses proteins through ice formation and freeze-concentration. No label we checked tells users to freeze the powder either.
| Product | Label statement |
|---|---|
| Ozempic | Do not freeze; do not use if it has been frozen. Do not store in the freezer or next to the cooling element. |
| Wegovy | Do not freeze; do not use if it has been frozen. |
| Mounjaro / Zepbound | Do not freeze; do not use if frozen. |
| Saxenda / Victoza | Do not freeze; do not use if it has been frozen. Not next to the cooling element. |
| Norditropin | Do not freeze; do not use Norditropin that has been frozen. |
| Genotropin, Omnitrope | Do not freeze. |
| Humatrope | Avoid freezing the diluent and the reconstituted cartridge. |
| Pregnyl, Fresenius hCG (mixed) | Do not freeze. |
| Egrifta SV | Do not store, freeze or refrigerate after mixing. |
| Egrifta WR | Do not freeze; do not freeze or refrigerate after mixing. |
The Novarel label has no freeze statement; it says to refrigerate the mixed product. Absence of a warning is not a freezing instruction.
Published pharmaceutical research names three main stresses during freezing: low temperature, freeze-concentration (solutes and the drug concentrate as water turns to ice) and ice formation itself (Bhatnagar 2007). Reviews of liquid protein drugs list freeze-thawing among the stresses that cause instability (Manning 2010). Frozen-then-thawed is a different product from the one that was tested.
Yes. Lyophilized powder has already been freeze-dried under controlled conditions; that is how many proteins reach an acceptable shelf life (Wang 2000). The labels store it either refrigerated (Genotropin cartridges, Humatrope, Omnitrope) or at room temperature (Novarel, Pregnyl, Egrifta SV and WR, Genotropin MiniQuick up to 3 months). None of the labels we checked tells users to put the powder in a home freezer.
For research peptides, no FDA label covers these, and we found no published study of how long the mixed vial stays stable in a fridge. Long-term freezer storage of research powder is common advice online, but we found no peer-reviewed study that tests it for these peptides. See how long mixed peptides last.