Neurotoxin Reconstitution Guide
By Stcki · 7 min read · February 2026
Reconstitution is the process of adding saline to a powdered neurotoxin vial to create an injectable solution. Each of the six FDA-approved neurotoxins — Botox, Dysport, Xeomin, Jeuveau, Daxxify, and Letybo — has specific dilution protocols from its manufacturer. Getting the ratio right determines your concentration (units per 0.1mL), which directly affects dosing accuracy, injection control, and waste. All products use preservative-free 0.9% Sodium Chloride and must be used within 24 hours after reconstitution.
The universal rules
- Use preservative-free 0.9% Sodium Chloride Injection, USP.
- Inject the saline slowly down the inside wall of the vial. Never squirt it directly onto the powder.
- Gently swirl or rotate the vial to dissolve. NEVER shake. Shaking denatures the botulinum toxin protein.
- Check for vacuum when piercing the stopper. If there's no vacuum, the seal is compromised — discard the vial.
- Inspect the solution. It should be clear, colorless, and free of particulate matter.
- Label immediately. Product name, concentration, date/time of reconstitution, and expiration.
- Use within 24 hours. No exceptions.
- Single-patient use only. Discard unused portions.
Botox (onabotulinumtoxinA) — Allergan/AbbVie
Available in 50-unit and 100-unit vials.
| Vial Size | Saline Added | Units per 0.1mL | Units per 1mL |
|---|---|---|---|
| 100U | 2.5mL | 4.0 U | 40 U |
| 100U | 2.0mL | 5.0 U | 50 U |
| 100U | 1.0mL | 10.0 U | 100 U |
| 50U | 1.25mL | 4.0 U | 40 U |
Storage: Refrigerate 2-8°C. Do not freeze reconstituted product. Use within 24 hours. Maximum cumulative dose: 400 units in a 3-month interval.
Dysport (abobotulinumtoxinA) — Galderma
300-unit and 500-unit vials. Conversion: approximately 2.5–3 Dysport units per 1 Botox unit (units are not interchangeable between products).
| Vial Size | Saline Added | Units per 0.1mL | Units per 1mL |
|---|---|---|---|
| 300U | 1.5mL | 20 U | 200 U |
| 300U | 2.5mL | 12 U | 120 U |
| 500U | 1.0mL | 50 U | 500 U |
| 500U | 2.5mL | 20 U | 200 U |
Contains human albumin. Contraindicated in patients with cow's milk protein allergy. Protect from light. Refrigerate 2-8°C.
Xeomin (incobotulinumtoxinA) — Merz
The "naked" neurotoxin — no complexing proteins. Available in 50-unit and 100-unit vials.
| Vial Size | Saline Added | Units per 0.1mL | Units per 1mL |
|---|---|---|---|
| 100U | 2.5mL | 4.0 U | 40 U |
| 100U | 2.0mL | 5.0 U | 50 U |
| 50U | 1.25mL | 4.0 U | 40 U |
Can be stored at room temperature for up to 36 months before reconstitution — unique among neurotoxins. After reconstitution, use within 24 hours (refrigerated).
Jeuveau (prabotulinumtoxinA-xvfs) — Evolus
Purpose-built for aesthetic use. Available in 100-unit vials.
| Vial Size | Saline Added | Units per 0.1mL | Units per 1mL |
|---|---|---|---|
| 100U | 2.5mL | 4.0 U | 40 U |
| 100U | 2.0mL | 5.0 U | 50 U |
Refrigerate at 2-8°C. Use within 24 hours after reconstitution.
Daxxify (daxibotulinumtoxinA-lanm) — Revance
Longest-lasting neurotoxin (6–9 months). Uses novel peptide stabilizer instead of human albumin.
| Vial Size | Saline Added | Units per 0.1mL | Units per 1mL |
|---|---|---|---|
| 100U | 0.6mL (FDA) | 16.7 U | 167 U |
| 100U | 1.2mL (common) | 8.3 U | 83 U |
Can be stored at room temperature before reconstitution. FDA-approved glabella dose is 40 units. After reconstitution, use within 24 hours.
Letybo (letibotulinumtoxinA-jcdb) — Hugel/Evolus
Newest FDA-approved neurotoxin (2024). High purity, low protein load. Available in 50-unit and 100-unit vials.
| Vial Size | Saline Added | Units per 0.1mL | Units per 1mL |
|---|---|---|---|
| 100U | 2.5mL | 4.0 U | 40 U |
| 50U | 1.25mL | 4.0 U | 40 U |
Refrigerate at 2-8°C. Use within 24 hours after reconstitution.
Quick comparison: All 6 products at a glance
| Product | Manufacturer | Vial Sizes | Common Dilution | Units/0.1mL | Storage | Duration |
|---|---|---|---|---|---|---|
| Botox | AbbVie/Allergan | 50U, 100U | 2.5mL per 100U | 4.0 U | Refrigerate 2-8°C | 3-4 months |
| Dysport | Galderma | 300U, 500U | 1.5mL per 300U | 20 U | Refrigerate 2-8°C | Up to 4 months |
| Xeomin | Merz | 50U, 100U | 2.5mL per 100U | 4.0 U | Room temp OK (36mo) | 3-4 months |
| Jeuveau | Evolus | 100U | 2.5mL per 100U | 4.0 U | Refrigerate 2-8°C | 3-4 months |
| Daxxify | Revance | 100U | 0.6mL per 100U | 16.7 U | Room temp OK | 6-9 months |
| Letybo | Hugel/Evolus | 50U, 100U | 2.5mL per 100U | 4.0 U | Refrigerate 2-8°C | 3-4 months |
Frequently Asked Questions
How do you reconstitute Botox?
Add preservative-free 0.9% Sodium Chloride to the vial. For a 100-unit vial, 2.5mL of saline yields 4 units per 0.1mL. Inject saline slowly down the inside wall, gently swirl to dissolve, and use within 24 hours.
How do you reconstitute Dysport?
Add 1.5mL of preservative-free saline to a 300-unit vial for 20 units per 0.1mL, or 2.5mL for 12 units per 0.1mL.
How do you reconstitute Daxxify?
Add 0.6mL of saline to a 100-unit vial (FDA-approved dilution) for 16.7 units per 0.1mL. Many practices use 1.2mL for easier handling.
Can you shake a neurotoxin vial during reconstitution?
No. Never shake a neurotoxin vial. Shaking can denature the botulinum toxin protein, reducing its effectiveness.
How long does reconstituted neurotoxin last?
All six FDA-approved neurotoxins must be used within 24 hours after reconstitution. Store refrigerated at 2-8°C.
What if there is no vacuum when you pierce a neurotoxin vial?
Discard the vial. The seal has been compromised, risking contamination.
What is the difference between bacteriostatic saline and normal saline?
FDA prescribing information specifies preservative-free 0.9% Sodium Chloride. Bacteriostatic saline contains benzyl alcohol and may reduce injection discomfort. Follow your medical director's protocol.