Lyophilised peptides are remarkably stable in dry form. The problem isn't dryness — it's the transit environment: vans sit in 35 °C summer heat or freeze in winter sorting facilities. Repeated thermal cycling slowly degrades sensitive sequences even before reconstitution.
Which peptides need cold-chain
- GLP-1 class (Semaglutide, Tirzepatide, Retatrutide)
- Larger / longer sequences (HGH, Tesamorelin, CJC-1295 DAC)
- Anything you're buying in bulk and will store long-term
Which peptides are fine without
- Short, stable sequences (BPC-157, TB-500, GHK-Cu)
- Quick local UK shipping in cool months
What our upgrade adds
Our Cold-Chain Shipping Upgrade (£15) replaces the standard mailer with an insulated foam box, a phase-change gel pack pre-chilled to 4 °C, and a temperature-tracking indicator card. Total transit stays under 8 °C for up to 48 hours.
For sensitive bulk orders, this is the cheapest insurance you can buy.