Botulinum toxin type B (MyoBloc) in the management of hyperkinetic facial lines

OBJECTIVE: Our goal was to evaluate the safety and efficacy of botulinum toxin type B (BTX-B) in the management of hyperfunctional facial lines. STUDY DESIGN AND SETTING: Twenty-four patients from an academic faculty practice were treated with 400 to 800 units BTX-B in the corrugator, orbicularis oculi, or frontalis. Patients were evaluated with the Wrinkle Improvement Score (WIS) and Rated Numeric Kinetic Line Scale (RNKLS) and questioned about side effects and pain. Evaluations were made at 1, 2, 4, 8, and 12 weeks. RESULTS: Onset Of effect was within 72 hours. WIS and RNKLS for all sites were statistically better after treatment, with the effect lasting 8 weeks, In general, patients noted a moderate improvement (grade 2) on WIS and a 2-point improvement on RNKLS. Injection was more painful than that of BTX-A. There were no complications. CONCLUSION: BTX-B is a safe and effective technique to eliminate wrinkles. Further studies are needed to elucidate dosage and duration. SIGNIFICANCE: BTX-B is stable for prolonged periods of time, requires no preparation before use, and is antigenetically distinct from BTX-A.