What is the efficacy of Botulinum toxin (Botox) for treating crow's feet (lateral canthal lines)?

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From the Research

Botulinum toxin is a highly effective treatment for crow's feet, with a recommended dose of 12 units per side, as evidenced by the study published in 2005 1. The treatment of crow's feet with botulinum toxin has been extensively studied, with various formulations and dosing regimens evaluated.

  • The most commonly used formulations include Botox (onabotulinumtoxinA), Dysport (abobotulinumtoxinA), and Xeomin (incobotulinumtoxinA).
  • Typical dosing ranges from 10-15 units of Botox (or equivalent) per side, injected in 3-5 small amounts around the lateral orbital rim.
  • The procedure takes only minutes to perform, with results appearing within 3-7 days and lasting approximately 3-4 months.
  • Side effects are generally mild and temporary, including possible bruising, asymmetry, or eyelid drooping if injected incorrectly.
  • Botulinum toxin works by temporarily blocking nerve signals to the orbicularis oculi muscles that cause these wrinkles, resulting in smoother skin appearance when expressing.
  • The treatment is most effective for dynamic wrinkles (those that appear with facial movement) rather than static lines that are present at rest, though repeated treatments may gradually improve even static lines.
  • For optimal results, treatments should be repeated before the full effect wears off, typically every 3-4 months, as supported by the study published in 2009 2 and 2011 3.
  • A more recent study published in 2015 4 highlights the importance of individualizing dosage based on patient anatomy, muscle mass, and desired outcome.
  • Additionally, a study from 2004 5 demonstrated the safety and efficacy of botulinum toxin A in treating crow's feet wrinkles, with a clear improvement shown at 6 months.

References

Research

Double-blind, randomized, placebo-controlled, dose-response study of the safety and efficacy of botulinum toxin type A in subjects with crow's feet.

Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.], 2005

Research

Efficacy and safety of botulinum toxin type A in the treatment of lateral crow's feet: double-blind, placebo-controlled, dose-ranging study.

Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.], 2009

Research

[Treatment of crow's feet with two different botulinum toxin type A preparations in split-face technique].

Der Hautarzt; Zeitschrift fur Dermatologie, Venerologie, und verwandte Gebiete, 2011

Research

Botulinum toxin A: a 9-month clinical and 3D in vivo profilometric crow's feet wrinkle formation study.

Journal of cosmetic and laser therapy : official publication of the European Society for Laser Dermatology, 2004

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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