Recommended Botulinum Toxin (Botox) Dosing per 0.01 mL
The standard dosing of botulinum toxin (Botox) is 4 Units per 0.1 mL, which equals 0.4 Units per 0.01 mL for cosmetic applications such as glabellar lines. 1
Dosing Considerations
- The FDA-approved dose for Jeuveau (prabotulinumtoxinA-xvfs) for glabellar lines is 0.1 mL (4 Units) injected intramuscularly into each of five sites, for a total dose of 20 Units 1
- This translates to a concentration of 0.4 Units per 0.01 mL when properly reconstituted 1, 2
- Botulinum toxin is extremely potent, with a specific toxicity in mice of 3 × 10^7 U/mg in crystalline form 3
- The human LD50 for inhalation botulism is estimated at 1-3 nanograms of toxin per kilogram of body weight, highlighting the importance of precise dosing 4
Preparation and Administration
- Botulinum toxin must be reconstituted with preservative-free 0.9% sodium chloride 2
- Once reconstituted, the solution should be used within four hours as it contains no preservatives 2
- The reconstituted solution must be stored in a refrigerator until use 2
- Proper preparation is critical as the potency units of different botulinum toxin products are not interchangeable 1, 5
Safety Considerations
- The effects of botulinum toxin may spread from the injection site, potentially causing symptoms consistent with botulinum toxin effects 1
- These symptoms have been reported hours to weeks after injection 1
- Swallowing and breathing difficulties can be life-threatening, and there have been reports of death 1
- In the event of overdose or adverse effects, botulinum antitoxin is the specific antidote, which works by binding and neutralizing circulating toxin 6
Dosing Variations
- Therapeutic doses vary widely from 1.25 Units to 100 Units depending on the treatment site and indication 2
- Higher doses (>400 Units per session) may be used in certain conditions like dystonia and spasticity, with studies showing continued benefit and no serious adverse effects in appropriate patients 7
- Initial doses should be conservative for patients without previous botulinum toxin treatment 2
- Subsequent doses should be individualized based on patient response, with larger repeat doses often used when the initial response is insufficient 2
Different Preparations
- Available therapeutic preparations include Botox, Dysport, Xeomin (type A), and NeuroBloc/Myobloc (type B), each with different specific biological activities 5
- The specific biological activity (potency per nanogram) varies: 60 for Botox, 100 for Dysport, 167 for Xeomin, and 5 for NeuroBloc 5
- These differences in potency mean that dosing is not directly interchangeable between products 1, 5