How Long Does Reconstituted Tesamorelin Remain Stable for Research Use?

Tesamorelin ships as a freeze-dried powder specifically because that form protects the 44-amino-acid chain from the degradation pathways that become active once water is reintroduced. At −20°C, sealed and desiccated, the lyophilized powder remains stable for extended periods.

Once reconstituted, refrigeration at 2–8°C slows — but doesn't stop — the gradual degradation process, which is why reconstituted solution has a materially shorter usable window than the dry powder. Bacteriostatic water's benzyl alcohol content protects against microbial contamination during this window but doesn't extend the peptide's own chemical stability indefinitely.

A reconstituted solution that shows cloudiness, discoloration, or visible particulate should be treated as unusable regardless of elapsed time — basic visual inspection before use is standard laboratory practice for any reconstituted peptide.