2-3 months. Plenty of reports out there using 6 month bact water reconstituted 10mg PT-141 vials.... Use within 2 months would be my recommendation. Preference is the a 2mg PT-141 peptide currently. Take what I want, pitch the remainder
Melanotan peptides (MT-II, PT-141) are very durable. "...stability of the MTII at 37 degrees C (98 degrees Fahrenheit) for at least 28 days has been documented in literature ."