Understand the source comparison
Manufacturer expiration dates vs reality
What expiration dates mean: Conservative estimate of guaranteed potency Usually based on accelerated stability testing Designed to ensure 90-100% potency through date Regulatory and liability considerations Why stated dates are conservative: Expensive to test
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This page preserves a source comparison for education. It does not add a rating, recommendation or clinical judgment.
- What expiration dates mean:
- Conservative estimate of guaranteed potency
- Usually based on accelerated stability testing
- Designed to ensure 90-100% potency through date
- Regulatory and liability considerations
- Why stated dates are conservative:
- Expensive to test long-term (years)
- Manufacturers want safety margin
- Better to underestimate than overestimate
- Varies by company (research chemicals vs pharma)
- Research peptide "expiration":
- Often no formal expiration date
- COA (Certificate of Analysis) shows testing date
- General rule: 2 years from COA date if frozen
- 6-12 months from COA if refrigerated
- Real-world peptide longevity:
- Frozen peptides often remain 80%+ potent at 3-5 years
- Refrigerated peptides good 12-18+ months if properly stored
- Much depends on storage conditions and handling
- When to trust peptides past "expiration":
- Stored frozen continuously: Very likely still good
- Stored refrigerated: Probably good if within 1-2 years
- Room temp storage: Don't trust past weeks
- Visual inspection passes (see below)
- COA relatively recent (within 2-3 years)
- When to discard despite date:
- Visible discoloration or changes
- Exposed to heat or temperature extremes
- Stored at room temperature for extended period
- Seal broken (contamination risk)
- Smell or visual contamination