What is the recommended dosage of Myobloc (botulinum toxin) for treating glabella frown lines?

Recommended Dosage of Myobloc (Botulinum Toxin B) for Glabella Frown Lines

The recommended dosage of Myobloc (botulinum toxin B) for treating glabellar frown lines is 2,400-3,000 units divided among 5-6 injection sites in the glabellar region.

Dosing Guidelines for Myobloc (BTX-B)

Myobloc (botulinum toxin B) requires significantly higher unit dosing compared to botulinum toxin A products due to differences in potency and mechanism of action. Based on clinical research:

• Starting dose range: 2,400-3,000 units total 1
• Injection sites: Typically divided among 6 sites in the glabellar region
• Onset of action: Rapid, with full response typically seen within 2-3 days 1
• Duration of effect:
  • At 2,400 units: approximately 9.6 weeks
  • At 3,000 units: approximately 10.4 weeks 1

Administration Technique

For optimal results when injecting Myobloc for glabellar lines:

1. Divide the total dose equally among injection sites (typically 5-6 points)
2. Inject into the following muscles:
   • Corrugator supercilii muscles (2 sites in each muscle)
   • Procerus muscle (1-2 sites)
3. Ensure proper needle placement to avoid complications:
   • Place lateral corrugator injections at least 1 cm above the bony supraorbital ridge
   • Do not inject closer than 1 cm above the central eyebrow
   • Use proper aseptic technique

Comparison with Botulinum Toxin A Products

It's important to note that Myobloc (BTX-B) dosing is significantly different from botulinum toxin A products:

• Botulinum toxin A (Botox Cosmetic) typically requires only 20 units total for the same area 2
• The higher unit requirement for Myobloc does not indicate greater potency, but reflects differences in formulation and biological activity

Safety Considerations

When administering Myobloc for glabellar lines, be aware of:

• Common adverse effects: Mild pain at injection site, potential for headache 1
• Less common adverse effects: Eyelid ptosis (reported in approximately 2-3% of patients) 1
• Post-administration care:
  • Patients should remain upright for 3-4 hours after treatment
  • Avoid touching or massaging treated areas
  • Refrain from strenuous exercise for 24 hours
  • Avoid alcohol consumption for 24 hours 3

Clinical Pearls

• The critical period for potential toxin spread is within the first 24-48 hours after injection 3
• Higher doses of Myobloc appear to prolong the duration of response with minimal increase in adverse effects 1
• Pain during injection may be reduced using a skin-vibrating device, cold air skin cooling, or topical anesthetics 3
• Reconstituted botulinum toxin should be stored properly and used according to manufacturer guidelines

Conclusion

While Myobloc (botulinum toxin B) is effective for treating glabellar frown lines, it requires significantly higher unit dosing compared to botulinum toxin A products. The recommended dosage of 2,400-3,000 units provides approximately 9-10 weeks of effect with an acceptable safety profile.