Lidocaine Iontophoresis Versus EMLA Cream for CO2 Laser Treatment in Seborrheic Keratosis
Rosaya Phahonthep MD*, Wannasri Sindhuphak MD*, Pin Sriprajittichai MD**
Affiliation : *Department of Medicine, Faculty of Medicine, Chulalongkorn University **Department of Anesthesiology, Faculty of Medicine, Chulalongkorn University
Background : Topical anesthesia for skin surgery has widely been used for a long time. Various preparations are used. The
EMLA cream is the most popular one.
Objective : The authors compared the local analgesic effect of topical lidocaine iontophoresis and EMLA cream in a cross-
over study design.
Method : After informed consent, 16 patients with seborrheic keratosis, who required CO2 laser surgery, were enrolled.
Two lesions on the opposite side of the body with a comparable size, shape and location were selected from each patient. The
lidocaine iontophoresis was done on one lesion and the EMLA cream was applied on the other. The CO2 laser surgery was
performed after 10 min of lidocaine iontophoresis and 60 min after EMLA cream. The level of pain was recorded using a
100-mm visual analog scale. Ratings of patient satisfaction were also assessed.
Results : There were no significant differences in pain scores between the two groups (p=0.968), but significantly higher in
satisfaction scores(1-5 scale) in the iontophoretic group than the EMLA group(p=0.005). Fifteen patients preferred
lidocaine iontophoresis(93.8%), none preferred EMLA cream. All patients in the present study tolerated the tingling and
burning sensations. No severe adverse events and side effects were detected.
Conclusion : Lidocaine iontophoresis provides effective pain relief for CO2 laser surgery of seborrheic keratosis as well
as the EMLA cream. The effect is as fast as 10 min after application. There is no significant side effect. Most of the patients
were satisfied. Lidocaine iontophoresis is a useful, noninvasive local anesthesia for CO2 laser surgery of superficial skin
lesions.
Keywords : EMLA, Lidocaine, Iontophoresis, Seborrheic keratosis, Carbondioxide laser.
