Tesamorelin Storage Guide
Critical storage instructions for reconstituted Tesamorelin (EGRIFTA®). Unlike most peptides, Tesamorelin requires room temperature storage — refrigeration causes gelation.
Critical: Do NOT Refrigerate Reconstituted Tesamorelin
Unlike most peptides, reconstituted Tesamorelin gels/precipitates at cold temperatures. Store at room temperature (20–25°C) and use within 7 days. Do NOT freeze. This is counterintuitive but manufacturer-specified.
⚡ Quick Reference
Reconstitute with Bacteriostatic Water → Store at 20–25°C (68–77°F) → Use within 7 days → Do NOT refrigerate or freeze. Solution must be clear and colorless — discard if cloudy, gelled, or particulate.
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Temperature Effects
🧊 Why Room Temperature?
Tesamorelin’s solubility decreases at cold temperatures, causing the peptide to precipitate or form a gel-like solid. This is a physical stability issue — the peptide literally falls out of solution when cold.
While most peptides are chemically more stable when refrigerated, Tesamorelin’s formulation and concentration make cold storage problematic. The manufacturer chose room-temperature storage to prevent precipitation while maintaining acceptable stability for 7 days.
If gelled: Warming back to room temp sometimes redissolves mild precipitates, but full “gelling” indicates significant aggregation that likely cannot be reliably reversed. Discard and reconstitute fresh.
Diluent Comparison
The choice of diluent affects both usability and storage duration. The manufacturer supplies and recommends bacteriostatic water for multi-dose use.
💧 Bacteriostatic Water
The recommended diluent for multi-dose use. Benzyl alcohol suppresses bacterial growth, allowing the solution to be used for multiple injections over several days.
Clinical kits (EGRIFTA WR™) are supplied with a 30 mL bottle specifically for weekly reconstitution.
💉 Sterile Water
Used in single-use vials (EGRIFTA SV®). Contains no antimicrobial agent — use immediately and discard any remainder.
Even refrigeration will not safely extend usable life due to risk of microbial growth. Only appropriate if using full vial within hours.
Note on Benzyl Alcohol: While BA extends usability, it can mildly accelerate peptide aggregation over time — one reason the solution is discarded after 1 week despite the preservative. Patients sensitive to benzyl alcohol may need sterile water with immediate use.
Normal Saline (0.9% NaCl): Not provided by manufacturer. Plain saline lacks preservative (same single-use rule as sterile water). Bacteriostatic saline would work similarly to bac water. Stick with Water for Injection as recommended.
Storage Timeline
📅 7-Day Maximum
After reconstitution with bacteriostatic water, use within 7 days. This is an official stability guideline based on studies of the drug’s integrity and preservative effectiveness. Any unused solution should be discarded after 7 days.
📦 Lyophilized (Dry) Stability
Unreconstituted powder is much more stable. Store per manufacturer instructions — newer formulations are room-temp stable.
For long-term storage (months/years), refrigeration or freezing of dry powder is acceptable. Always protect from moisture and light.
🔬 Extended Storage (Research Only)
If longer storage needed: aliquot into sterile single-use portions and freeze at –20°C. Each aliquot thawed only once.
Not FDA-approved practice for human use. Thawed peptide may still aggregate or lose potency.
Signs of Degradation
✅ Acceptable: Clear & Colorless
Tesamorelin in solution should be clear, colorless, and free of any particles. This is the only acceptable state for injection. Inspect every time before use.
❌ Do NOT Use If:
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Cloudy or hazy appearance
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Gel-like consistency or clumps
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Visible particles, fibers, or threads
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Color change (oxidation/contamination)
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Past 7 days since reconstitution
🔍 Inspection Tips
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Hold vial against light source
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Gently swirl (don’t shake) and observe
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Check for any floating particles
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Verify solution flows freely (not viscous)
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When in doubt, discard and reconstitute fresh
Never inject a solution that has visible particles, cloudiness, or gel-like consistency. This indicates significant aggregation that may be harmful and the peptide has likely lost potency.
Storage Checklist
✓ Do’s
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Use Bacteriostatic Water for multi-dose reconstitution
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Store at room temperature (20–25°C / 68–77°F)
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Keep in original container to protect from light
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Use within 7 days of reconstitution
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Inspect before each use — must be clear and colorless
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Label vial with reconstitution date
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Discard unused portion after 7 days
✗ Don’ts
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Do NOT refrigerate reconstituted solution — causes gelation
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Do NOT freeze reconstituted solution — irreversible damage
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Do NOT shake vigorously — can cause aggregation
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Do NOT store sterile water reconstitution — use immediately
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Do NOT inject if cloudy, gelled, or particulate
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Do NOT use past 7-day expiration
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Do NOT expose to extreme heat or direct sunlight
FAQ
Bottom line: Reconstituted Tesamorelin requires room temperature storage (20–25°C) — this is counterintuitive but critical. Use bacteriostatic water for multi-dose, use within 7 days, and never refrigerate or freeze the solution. Always inspect for clarity before injection. This unique storage requirement is the key difference from most other peptides.