📑 Contents
Why is storage so important?
Peptides are sensitive molecules. Incorrect storage can:
⚠️ Consequences of improper storage
- Destroy effectiveness — The molecule breaks down
- Reduce shelf life — Shorter usage period
- Cause contamination — Bacterial growth
- Provide unreliable results — Varying dose per administration
Basic rules for all peptides
🌡️ 1. Temperature
| Condition | Temperature | Shelf Life |
|---|---|---|
| Unopened/lyophilized | 2-8°C (refrigerator) | 12-24 months |
| Reconstituted (mixed) | 2-8°C (refrigerator) | 28-30 days |
| Room temperature | 15-25°C | Max a few hours |
☀️ 2. Light
Peptides are light-sensitive:
- Store in original packaging or a dark container
- Avoid direct sunlight
- Fluorescent lighting can also affect them
💧 3. Moisture
Lyophilized peptides are extremely sensitive to moisture:
- Do not open the packaging until ready to use
- Store with silica gel packets if possible
- Work quickly during reconstitution
Storage before mixing
Unopened lyophilized powder:
📦 Storage options
- Best option: Refrigerator (2-8°C)
- Acceptable: Freezer (-20°C) for long-term storage
- Avoid: Room temperature longer than transport
💡 Tip
Allow the peptide to reach room temperature BEFORE opening to avoid condensation on the powder.
Storage after mixing
Reconstituted peptide requires extra caution:
✓ Use BAC water
Bacteriostatic water contains preservatives (benzyl alcohol) that prevent bacterial growth. With BAC water, the solution lasts 28-30 days.
Sterile water as an alternative
If using sterile water without preservatives:
- Shelf life: Max 7-10 days
- Requires stricter sterile technique
- Less forgiving if contaminated
Specific peptides
| Peptide | Lyophilized | Mixed | Note |
|---|---|---|---|
| Semaglutide | Refrigerator, 12+ months | Refrigerator, 28 days | Sensitive to agitation |
| Retatrutide | Refrigerator or freezer | Refrigerator, 28 days | Same as Semaglutide |
| Tirzepatide | Refrigerator | Refrigerator, 28 days | Relatively stable |
📖 Learn more about Semaglutide →
Common mistakes to avoid
❌ Mistake 1: Storing in the refrigerator door
Problem: Temperature fluctuates the most here when opened.
Solution: Place at the back of the refrigerator.
❌ Mistake 2: Freezing reconstituted peptide
Problem: Ice crystals permanently destroy the molecular structure.
Solution: NEVER freeze mixed peptide.
❌ Mistake 3: Using an expired solution
Problem: Effectiveness decreases, risk of contamination.
Solution: Discard after 28-30 days, regardless of appearance.
❌ Mistake 4: Exposure to direct sunlight
Problem: UV radiation rapidly degrades the peptide.
Solution: Dark storage, original packaging.
Transport and travel
Traveling with peptides requires planning:
Short trip (1-2 days)
- Cooler bag with ice packs
- Avoid direct contact between ice and vial
- Monitor temperature with a thermometer
Longer trips
- Medical cooler with temperature control
- Frozen ice packs that are replaced
- Consider taking lyophilized and mixing on-site
How do you know if the peptide is damaged?
Signs of degradation:
🔍 Warning signs
- Cloudy solution — Should be crystal clear
- Particles or flakes — Signs of breakdown
- Changed color — Should be colorless
- Strange odor — May indicate contamination
- Reduced effect — Clearest sign
💡 Rule
When in doubt — discard and use new. Your health is more important than the cost.
Practical tips
✓ Label your vials
Write on each vial:
- What it is
- Date of mixing
- Concentration (mg/ml)
- Expiration date
Organize the refrigerator
- Have a dedicated drawer for peptides
- Store away from food
- Keep track of what is opened/unopened
Summary
✓ 6 golden rules
- Always refrigerate — 2-8°C is optimal
- Dark — Protect from light
- Never freeze mixed peptide
- 28 days max — after mixing
- Use BAC water — for best shelf life
- In doubt? Discard.