Does botulinum toxin (Botox) injection near the mouth cause pain?

Pain Associated with Botulinum Toxin Injections Near the Mouth

Botulinum toxin injections near the mouth can cause pain during administration, but the pain is typically mild, transient, and can be minimized with proper techniques.

Pain During Injection

• Botulinum toxin injections are commonly associated with localized pain at the injection site, which is typically brief and occurs during the administration process 1
• Pain sensation is primarily related to the needle penetration and the injection process itself rather than the toxin 2
• Localized pain, inflammation, tenderness, swelling, erythema, and/or bleeding/bruising may be associated with the injection 2

Pain Intensity and Duration

• Most adverse reactions, including pain, occur within the first week following injection of botulinum toxin and are generally transient 2
• Different botulinum toxin formulations may cause varying levels of pain:
  • Type B botulinum toxin (Neurobloc) causes significantly more injection pain than Type A formulations (Botox, Dysport) 3
  • No significant differences in pain levels have been found between different Type A formulations (Botox and Dysport) 3

Pain Reduction Techniques

• Several methods can be used to decrease the pain associated with botulinum toxin injections near the mouth:

  • Slow rate of infiltration 1
  • Vibration of the skin using a skin-vibrating device 1
  • Use of a warm solution 1
  • Cold air skin cooling 1

• The American Academy of Dermatology guidelines specifically recommend the use of a skin-vibrating device to help decrease the pain of botulinum toxin injection (Level of evidence: II, Strength of recommendation: B) 1

Local Anesthetics

• Local anesthetics can be used prior to botulinum toxin injection without affecting the efficacy of the toxin 4
• An experimental study showed that infiltration with local anesthetics (prilocaine, lidocaine, lidocaine with epinephrine) before botulinum toxin injection does not interfere with the effectiveness of the toxin 4

Other Potential Side Effects

• Beyond injection pain, other common adverse reactions include:

  • Headache (12% of patients) 2
  • Eyelid ptosis (2% of patients) 2
  • Upper respiratory tract infection (3% of patients) 2
  • Needle-related anxiety may result in vasovagal responses, including syncope and hypotension 2

• Serious but rare complications include:

  • Spread of toxin effects beyond the injection site 2
  • Dysphagia and breathing difficulties 2
  • Hypersensitivity reactions 2

Special Considerations for Perioral Injections

• When injecting near the mouth, caution should be used in patients with:
  • Inflammation at the proposed injection site 2
  • Excessive weakness or atrophy in the target muscles 2
  • Marked facial asymmetry 2
  • Deep dermal scarring 2
  • Thick sebaceous skin 2

Conclusion

• Pain from botulinum toxin injections near the mouth is generally mild and transient 2, 5
• Using proper injection techniques (slow injection, vibration, warm solution) can significantly reduce discomfort 1
• The benefits of treatment typically outweigh the brief discomfort of injection for most patients 1