EMLA® Cream Application without Occlusive Dressing before Upper Facial Botulinum Toxin Injection A Randomized, Double-Blind, Placebo-Controlled Trial

To assess the effect of EMLA® cream application without occlusive dressing on pain on needling (PN) and pain on injection (PI) felt during multiple botulinum toxin type A (BTA) injections for correction of hyperkinetic upper facial lines

A Prospective, randomized, double-blind, placebo-controlled clinical trial was conducted on 44 subjects seeking upper facial wrinkles correction. Either EMLA® or placebo cream without occlusive dressing was applied on each side of the upper face at least for 60 minutes prior to injections of BTA. PN and PI scores were measured with Visual Analog Scale (VAS).

Patients age ranged from 27 to 57 (mean=40.95) years. Mean PN score (3.46) was less than PI score (3.61) (non significant); the two scores were highly correlated (r: 0.63, P=0.000). While both PN and PI scores were less in the EMLA® (3.02 and 3.34, respectively) than those of placebo group (3.90 and 3.89, respectively), the difference was statistically significant only for PN score (P=0.000 for PN and P=0.06 for PI). Male subjects had less PN and PI scores than females which was not statistically significant (P=0.66 for PN and 0.63 for PI). Time intervals between the cream application and BTA injections (60 to 110 minutes; mean=73.02, SD=10.15) did not have significant effect on the pain scores.

EMLA® cream application without occlusive dressing significantly reduces PN associated with multiple BTA injections. Reduction of PI was not significant. Longer duration of EMLA® cream application (up to 110 minutes) did not show lower pain score in either type of the pain.