Efficacy and safety of onabotulinumtoxin A in the treatment of platysma prominence: A systematic review and meta-analysis of randomized clinical trials.

Summary

Across three randomized controlled trials (n=1003 ITT), onabotulinumtoxinA significantly improved both participant- and clinician-rated platysma prominence at 14, 60, and 120 days versus placebo, with markedly higher patient satisfaction. Safety signals (bruising, hemorrhage, dysphagia/dysphonia) did not differ from placebo.

Key Findings

• OnabotulinumtoxinA improved participant-rated P-APPS at days 14 (RR 3.64), 60 (RR 3.46), and 120 (RR 2.57), all p<0.01.
• Clinician-rated C-APPS also improved at days 14 (RR 4.03), 60 (RR 3.73), and 120 (RR 2.21), all p<0.01.
• Patient satisfaction was significantly higher at days 14 (RR 5.71), 60 (RR 5.56), and 120 (RR 5.29), all p<0.01.
• No significant differences in safety outcomes (bruising, hemorrhage, swallowing/talking difficulties) versus placebo.

Clinical Implications

Clinicians can offer onabotulinumtoxinA for platysmal bands with expectation of meaningful improvement up to 4 months and a safety profile comparable to placebo. Counseling should include the time course of effect and the need for repeat treatments.

Limitations

• Only three RCTs included; potential heterogeneity in injection techniques and dosing not fully explored.
• Follow-up limited to 120 days; long-term durability beyond 4 months remains uncertain.

Future Directions

Head-to-head comparisons across neurotoxins and dosing patterns, standardized outcome reporting, and longer-term follow-up to define durability and retreatment intervals.