Neurotoxin Adverse Reactions

The International Society of Aesthetic Plastic Surgeons reports that botulinum toxin type A treatments (BoNT/A) are the most popular noninvasive cosmetic dermatology treatment performed globally. However, there are a few adverse reactions that can occur. These include medication side effects, pain or infection at injection site, erythema, swelling, or unexpected outcomes related to technique. Aseptic technique during the treatment is paramount to avoid potential local infection and is the foundation for appropriate and safe treatment. However, just as important is knowledge and understanding of the facial musculature and function to achieve excellent outcomes and avoid potential undesired effects. BoNT/A mechanism of action causes relaxation of muscles; therefore, eyelid ptosis, lip asymmetry, and brow ptosis are problematic and commonly feared adverse effects by both practitioners and patients. Complications or adverse effects can be described as related to the medication, technique, and/or skin infection. This chapter will focus on common adverse effects and the options for correction.