Topical anesthetic agents in dermatologic surgery. A review

Efficacy of a Lidocaine-Impregnated Elastrator Band for Castration and Tail Docking in Lambs

The primary objective of this study was to demonstrate the non-inferiority between lidocaine-impregnated ligation bands (LLBs) and control bands (CBs) with respect to the efficacy of castration and tail docking. Secondary objectives were to compare castration and tail-docking success, evaluate local site reactions, and compare average daily gain (ADG) between the treatment groups. A total of 238 male lambs were enrolled and randomly assigned to receive LLBs or CBs on their tail and scrotum. Lambs were weighed, had a health assessment, and the band site was observed on -3, 7, 14, 21, 28, 35, and 42 days after the bands were applied. A linear regression model was built to assess average daily gain, whereas a repeated measures model was used to evaluate body weight differences at each of the measured timepoints. Furthermore, logistic regression models were used to evaluate associations with casting outcomes. Few differences were noted between treatment groups with respect to casting success for the scrotum and tail and ADG over the entire experimental period. Non-inferiority calculations demonstrated no differences in tail docking and scrotal casting success, with casting occurring for the majority of animals by d 21 and d 42 for castration and tail docking, respectively. However, lambs receiving LLBs gained more weight from d -3 to 7 (+0.03 kg/d; 95% CI: 0 to 0.07), which may be an indication of effective pain control during the first week following band application. Overall, the use of an LLB does not affect the time to successful casting of the tail and could improve short-term growth when compared to a control band. Further studies are needed to compare LLBs to multimodal methods of pain relief.

Lidocaine-Liposomes-A Promising Frontier for Transdermal Pain Management

(1) Background: We aim to develop novel gel formulations for transdermal drug delivery systems in acute and inflammatory pain therapy. (2) Methods: We induced inflammation by the injection of λ-carrageenan on the hind paw of 80 Wistar male rats. The animals were randomized into eight groups of 10 rats each: C (placebo gel), E (EMLATM), L (lidocaine 2%), L-CD (lidocaine + cyclodextrin 2.5%), L-LP (lidocaine + liposomes 1.7%), L-CS (lidocaine + chitosan 4%), L-CSh (lidocaine + chitosan hydrochloride), and L-CS-LP (lidocaine + chitosan + liposomes). The behavior response was determined with a hot plate, cold plate, and algesimeter, each being performed at 30, 60, 120, 180, and 240 min after pain induction. At the end of the experiment, tissue samples were collected for histological assessment. (3) Results: L-LP had the greatest anesthetic effects, which was proven on the cold plate test compared to placebo and EMLATM (all p ≤ 0.001). L-CS-LP had a significant effect on cold plate evaluation compared to placebo (p ≤ 0.001) and on hot plate evaluation compared to EMLATM (p = 0.018). (4) Conclusions: L-LP is a new substance with a substantial analgesic effect demonstrated by the cold plate in the first 120 min. Further studies with more animals are needed to determine the maximum doses that can be applied for a better analgesia with minimum side effects.

Comparative effectiveness of ice packs versus topical lidocaine-prilocaine mixture for pain control in laser hair removal of the axilla: A rater-blinded randomized controlled trial

BACKGROUND

Laser hair removal is associated with moderate acute pain.

OBJECTIVE

To compare effectiveness of ice pack to topical lidocaine-prilocaine for pain reduction during axillary laser hair removal.

METHODS

Participants were randomly assigned to receive topical anesthetic to one axilla and ice packs to the other before each of 3, monthly 810 nm diode laser sessions. The primary endpoint was participant-reported pain on the visual analog scale (VAS) immediately following and 5 minutes after laser session. Posttreatment erythema, overall edema, and perifollicular edema were assessed by 2 blinded photoraters. Skin temperatures, patient preferences, and adverse events were recorded.

RESULTS

Eighty-eight of 90 (98%) planned laser treatments were delivered and randomized. Participants reported higher VAS scores immediately after laser treatment with lidocaine-prilocaine compared to ice (P = .03). Five minutes after, participants reported higher VAS scores with ice (P = .03). After 53 of the 88 treatments (60.2%), participants reported preferring ice (P = .055). No serious adverse events were reported.

LIMITATIONS

All participants were Caucasian or Asian with Fitzpatrick skin type I to III and coarse dark axillary hair, which may limit generalizability.

CONCLUSIONS

While pain control with ice and topical anesthesia is associated with time after treatment, the 2 modalities do not differ in terms of degree of pain reduction associated with axillary laser hair removal.

Comparison of the onset, depth, and duration of cutaneous anesthesia between topical 10% lidocaine and EMLA creams: A randomized, intraindividual, comparative trial

BACKGROUND

The eutectic mixture of local anesthetics (EMLA) is an effective cutaneous anesthetic, although its application is time consuming and poses a risk of methemoglobinemia. Currently, the efficacy of topical 10% lidocaine cream is unclear.

OBJECTIVE

To compare the onset, anesthesia depth, and duration of topical 10% lidocaine and EMLA cream.

METHODS

The randomized, split-body, comparative trial performed on 40 participants who received a topical 10% lidocaine cream or EMLA on forearms for 15-150 min. Pain was stimulated using a 21-gauge needle insertion and evaluated with the Verbal Pain Score. Adverse effects were recorded.

RESULTS

EMLA conferred significantly better efficacy than 10% lidocaine (p < 0.001). For acceptable pain at 4-mm depth, the minimal application times were 40.88 and 45.38 min of EMLA and 10% lidocaine creams, respectively. With 60/120-min application, the maximal needle-insertion depths with acceptable pain were 6.61/9.47 mm (EMLA) and 6.01/8.94 mm (10% lidocaine). EMLA's anesthetic effect showed an early increase after removal which was sustained for 60-90 min. Both creams caused adverse effects, with EMLA showing higher proportions, although the differences were statistically insignificant.

CONCLUSION

The efficacy of EMLA was superior to 10% lidocaine cream, especially regarding anesthesia onset and duration.

Evaluation of eutectic lidocaine/prilocaine cream for jugular blood sampling in cats

OBJECTIVES

The study aimed to evaluate the efficacy of a eutectic lidocaine/prilocaine cream (EMLA cream; Astra Pharmaceuticals) in reducing pain and reaction to venepuncture during jugular blood sampling in cats after a 30-min topical application time.

METHODS

The study was a prospective, blind, controlled clinical trial. Eighteen healthy client-owned cats were randomly allocated to two study groups. All cats were clipped on the left jugular groove region and then, depending on the study group, either the placebo (liquid paraffin) or EMLA cream was applied to the region. The area was then kept protected for the next 30 mins. Except for the operator who administered the product, all operators were blinded to the study groups. Blood sampling was performed by an experienced operator and a stress score was assigned to each cat according to the reactions observed during the venepuncture. Also, the procedure was classified as being 'easy' or 'difficult' by the same operator.

RESULTS

A significantly reduced stress score was observed in cats that received the EMLA cream compared with those belonging to the placebo group (P = 0.048); withdrawal movements were observed in 1/9 cats treated with the EMLA cream vs 7/9 cats of the placebo group (P = 0.015). The jugular venepuncture was defined as easy in 1/9 cats that received the placebo and in 8/9 cats in the EMLA group (P = 0.015).

CONCLUSIONS AND RELEVANCE

The present study provides evidence for the efficacy of the EMLA cream after a 30-min application time for jugular venepuncture in cats, together with significantly reduced stress for patients. Therefore, this study supports the routine use of EMLA cream as good practice to enhance the welfare of cats and to simplify venepuncture procedures.

Influence of Topical Anesthesia on Superficial Sensitivity: A Double-Blind, Randomized, Placebo-Controlled Study on 48 Healthy Subjects

BACKGROUND

Topical anesthetics are used in noninvasive transdermal anesthesia to decrease the superficial pain sensation threshold during dermatologic surgery. Combined pain relief and sensitivity loss can avoid discomfort during the surgery.

OBJECTIVE

The aim of this placebo-controlled study was to compare the efficacy of 3 commonly used topical agents by collating loss of sensitivity over time.

MATERIALS AND METHODS

Three topical anesthetic creams, a topical anti-inflammatory cream, and a moisturizing cream were applied on the left volar forearm of each of the 48 healthy Caucasian participants. Sensitivity was assessed with the dynamic 2-point discrimination and the Semmes-Weinstein test at 0, 60, 90, 120, 150, and 180 minutes after cream application.

RESULTS

After 180 minutes, benzocaine showed a significantly lower 2-point discrimination reduction than lidocaine alone and a lidocaine and prilocaine mixture. Sensory threshold measurements by the Semmes-Weinstein test after 60 minutes revealed a significantly higher effect with lidocaine alone and with the lidocaine and prilocaine mixture than with benzocaine.

CONCLUSION

The authors found a stronger skin sensitivity reduction by the eutectic lidocaine and prilocaine mixture and lidocaine alone compared with benzocaine. We suggest increased discomfort reduction in topical anesthetic supported dermatologic surgery by the eutectic mixture and lidocaine alone.

Topical anesthetics for pediatric laser treatment

Topical anesthetic agent causes transient insensibility to pain in a limited area of skin, and provides effective anesthesia in a short onset time, short duration, with seldom local or systemic side effects on intact skin and is simple to use. Topical formulations may offer significant benefits for prevention of procedural pain. Currently, they are considered to be the most effective anesthesia for laser treatments. Unfortunately, there is no standard anesthetic technique for this procedure. Lasers are being widely used in numerous dermatological and esthetics treatments in childhood. The advancement of new knowledge in laser technology have contributed to the development of new lasers that are commonly used in a pediatric population, such as Pulsed Dye, Carbon-dioxide and Nd:YAG laser. The most commonly used topical anesthetics in young patients for minimally or moderately painful laser cutaneous procedures are Lidocaine, Prilocaine, Tetracaine gel and combinations thereof.

The effects and side effects of lidocaine tetracaine peel off on laser-assisted hair removal

Background:

Lidocaine 7%-tetracaine 7% is one of the combinations recently offered for performing laser-assisted hair removal. The aim of this study was to compare the effects of this combination with placebo on the side effects of laser-assisted hair removal.

Materials and Methods:

This clinical trial was carried out on 110 women who referred to Isfahan Spadana laser clinic for laser-assisted hair removal. Lidocaine 7%-tetracaine 7% was applied on one-half of the face, whereas placebo was applied on the other side to create local anesthesia, and after 30 min, the place was cleaned and investigated for complications (edema, erythema, and pallor); then laser therapy was begun. At the end of the therapy, the patients’ pain was estimated using Visual Analog Scale (VAS). The data were analyzed using SPSS software by Chi-square and paired t-tests.

Results:

The mean age of patients was 27.74 ± 10.8 years. Average levels of anesthesia at 30 min after using lidocaine 7%-tetracaine 7% and placebo based on VAS were 3.6 ± 1.4 and 8.4 ± 1.5, respectively (P = 0.001). In other words, patients felt less pain by using lidocaine 7%-tetracaine 7%. The frequency of complications in patients was not significantly different between the two groups.

Conclusion:

Considering the better effect of lidocaine 7%-tetracaine 7% compared to placebo and its minimal side effects, we can use it before performing laser-assisted hair removal.

Comparison of Topical Anesthetics for Radiofrequency Ablation of Achrocordons: Eutectic Mixture of Lignocaine/Prilocaine versus Lidocaine/Tetracaine

Introduction. Topical application of local anesthetics is currently considered to be the easiest, most effective, and convenient way for treatment of patients who may be undergoing superficial dermatosurgical procedures. Materials and Methods. This study compares the anesthetic potential of 2.5% lidocaine and 2.5% prilocaine topical cream with 7% lignocaine and 7% tetracaine combination cream for radio ablative dermatosurgery when applied, under occlusion, for 30 minutes. 40 subjects of achrocordons were enrolled in this split-side randomized trial. Result. The pain severity experienced by subjects in terms of visual analogue scale score was significantly lesser for lignocaine/tetracaine combination cream as compared to lidocaine/prilocaine combination. Conclusion. This small study proves the efficacy of lidocaine/tetracaine combination as a topical anesthetic cream when applied for a short time interval of 30 minutes. This will help a dermatosurgeon to perform various dermatological procedures in a better and efficient manner with a shorter waiting period for analgesia to set in.

The efficacy and safety of topical EMLA cream application for minor surgery of the adult penis

Background and Objectives:

A variety of surgical procedures of the penis can be performed under local anesthesia. We evaluated the efficacy and safety of EMLA cream anesthetic in such procedures.

Materials and Methods:

In total 330 adult patients were subjected to minor penile surgery including: Complete circumcision (73), short frenulum plasty (168), meatotomy (14), fulguration of penile warts (56) and fulguration of urethral (meatal) warts (19). The level of anesthesia obtained by EMLA cream application along with any adverse effects was recorded.

Results:

The use of EMLA on mucosal lesions provided excellent level of local anesthesia in almost all patients (245/246, 99.5%). Anesthesia of skin lesions was in part influenced by the site of application. Circumcision patients showed the lowest efficacy of the EMLA cream as the majority (~80%) required some form of further anesthesia until the completion of the procedure. No significant adverse effects were noted. A transient erythema was present in almost all mucosal applications.

Conclusions:

The topical anesthetic EMLA cream is a useful, efficient and safe tool for minor surgical procedures of the penis at the office setting, with the exception of circumcision, where an additional type of anesthesia is likely to be necessary. Side effects can be kept to a minimum when the suggested doses are respected (especially at mucosal application) and the time allowed for action is carefully tailored to the site of application and the type of procedure.

Preparation and evaluation of lidocaine hydrochloride-loaded TAT-conjugated polymeric liposomes for transdermal delivery

Transactivation transcriptional activator (TAT) peptides were conjugated on the octadecyl-quaternized, lysine-modified chitosan to form polymeric liposomes (TAT-PLs) with cholesterol for improving transdermal delivery of local anesthetic lidocaine hydrochloride (LID). In this study, the LID loaded TAT-conjugated polymeric liposomes (LID-TAT-PLs) have been successfully prepared. LID-TAT-PLs were characterized by determination of their particle size, polydispersity, morphology, drug encapsulation efficiency, drug release behavior in vitro, and storage-stability. The skin permeation of LID-TAT-PLs was examined using a Franz diffusion cell mounted with depilated mouse skin in vitro, and penetration of TAT-PLs was visualized by confocal laser scanning microscopy (CLSM). The results showed that LID-TAT-PLs were spherical in solution, with substantially smaller mean diameter (154.7±10.7 nm), higher encapsulation efficiency (80.05±2.64%) and better stability in contrast to conventional liposomes (CLs). From the in vitro skin permeation results, transdermal flux of LID-TAT-PLs was approximately 4.17 and 1.75 times higher than that of LID solution and LID CLs (P<0.05). CLSM studies also confirmed that TAT-PLs reached viable layers of the skin. Hence, the results indicate that LID-TAT-PLs are effective and potential alternative for the LID transdermal formulation.

Hemoglobin adducts of the human bladder carcinogen o-toluidine after treatment with the local anesthetic prilocaine

Prilocaine, a widely used local anesthetic, is metabolized to o-toluidine which is classified as human carcinogen. We aimed to assess the impact of prilocaine-treatment on hemoglobin adducts from o-toluidine. Blood samples were obtained before and 24h after receiving prilocaine local anesthesia (Xylonest, 100mg) from 20 head and neck surgery patients and 6 healthy volunteers. Hemoglobin adducts of o-toluidine and 4-aminobiphenyl were determined by gas chromatography/mass spectrometry. Hemoglobin adducts of o-toluidine were significantly increased 24h after 100mg prilocaine-treatment by 21.6+/-12.8ng/g hemoglobin (mean+/-S.D., N=26; P<0.0001). This corresponds to a 6-360-fold increase of o-toluidine adduct levels in 25 patients from 0.54+/-0.95ng/g before treatment to 22.0+/-13.2ng/g 24h after surgery (mean+/-S.D.). Because of an extremely high background level the increase was only 1.6-fold in one patient (40.9ng/g before and 64.4ng/g 24h after prilocaine injection). Current smoking had no influence on background values and on the increase of o-toluidine adducts. No treatment-related differences were seen in mean hemoglobin adduct levels of 4-aminobiphenyl which were significantly higher in smokers, 0.149+/-0.096ng/g (mean+/-S.D., N=8) as compared to nonsmokers 0.036+/-0.035ng/g (mean+/-S.D., N=16; P<0.01). In conclusion, prilocaine anesthesia leads to a massive increase of hemoglobin adducts of the carcinogenic arylamine o-toluidine. This implies a carcinogenic risk which should be taken into account in preventive hazard minimization.

A randomized, double-blind comparison of two topical anesthetic formulations prior to electrodesiccation of dermatosis papulosa nigra

BACKGROUND

Liposomal lidocaine 4% (L.M.X.4 cream, Ferndale Laboratories Inc., Ferndale, MI, USA) has been proposed as a more rapidly acting topical anesthetic than the eutectic mixture of lidocaine 2.5% and prilocaine 2.5% (EMLA cream, AstraZeneca LP, Wilmington, DE, USA) for venipuncture and laser procedures. However, their anesthetic efficacy has not been previously compared for electrosurgical destruction of superficial skin lesions.

OBJECTIVE

To test the hypothesis that L.M.X.4 and EMLA differ in anesthetic efficacy when applied under occlusion for 30 minutes prior to electrodesiccation of papules of dermatosis papulosa nigra.

METHODS

Forty adults were randomly assigned to treatment with either agent for 30 minutes under Tegaderm. The study drug was administered for an additional 30 minutes if the electrodesiccation of the first few papules was too painful.

RESULTS

One subject treated with EMLA versus none treated with L.M.X.4 experienced complete anesthesia after a single 30-minute application. Nineteen of 20 (95%) subjects treated with EMLA versus 18 of 20 (90%) subjects treated with L.M.X.4 required only a single application (p = .49). Pain scores after the initial 30-minute application (scale: 0 = none to 10 = very severe) were EMLA 3.3 +/- 2.2 (mean +/- SD) versus L.M.X. 4 2.9 +/- 2.0 (p = .46).

CONCLUSION

EMLA and L.M.X.4 provide comparable levels of anesthesia after a single 30-minute application under occlusion prior to electrodesiccation of superficial skin lesions.

Adverse effects of EMLA (lidocaine/prilocaine) cream and efficacy for the placement of jugular catheters in hospitalized cats

EMLA is a lidocaine/prilocaine cream used for topical analgesia in human pediatric patients. The purpose of this study was to establish the safety of EMLA in clinically ill cats, to measure systemic absorption and to determine whether EMLA reduced the need for sedation for the placement of jugular catheters. Thirty-one cats were randomized to either a placebo or EMLA cream group. Cream was applied to a 10 cm(2) area over the jugular vein, with 1h of occlusive dressing. Neither anesthetic was systemically absorbed in any cat, and no adverse clinical signs were observed. Struggling during catheter placement was less in the EMLA-treated cats compared to placebo, but did not reach significance (P = 0.06). Jugular catheters were successfully placed in 60% of EMLA-treated cats and 38% of placebo cats; this difference was not statistically significant and may not justify the added steps of EMLA cream administration for this purpose. However, EMLA does appear to be safe in clinically ill cats, and may be useful for other applications such as for skin mass removal or repeated venepuncture.

Randomized, Double-Blind, Placebo-Controlled Study Evaluating the Lidocaine/Tetracaine Patch for Induction of Local Anesthesia prior to Minor Dermatologic Procedures in Geriatric Patients

BACKGROUND

Topical anesthetics offer a noninvasive method of anesthesia.

OBJECTIVE

To evaluate the efficacy and safety of the lidocaine/tetracaine patch, a 1:1 (wt:wt) eutectic mixture of lidocaine and tetracaine, for local anesthesia before minor dermatologic procedures in geriatric patients.

METHODS

In a multicenter, randomized, double-blind, placebo-controlled study, 79 patients over the age of 65 years received a 30-minute application of either the lidocaine/tetracaine patch or placebo immediately before a shave biopsy or superficial excision. The primary measure of efficacy was patient assessment of procedural pain using the visual analog scale (VAS). Secondary efficacy end points included patient, investigator, and independent observer assessments.

RESULTS

There was a statistically significant difference (p = .041) in patient ratings of pain by VAS score in the active group (9.5 mm) compared with the placebo group (22.5 mm). None of the secondary end points showed a statistically significant difference between groups. No adverse events were reported.

CONCLUSION

The lidocaine/tetracaine patch is a safe and effective method for noninvasive induction of local anesthesia for minor dermatologic procedures in patients over the age of 65 years.

Evaluation of the S-Caine Peel for Induction of Local Anesthesia for Laser-Assisted Tattoo Removal: Randomized, Double-Blind, Placebo-Controlled, Multicenter Study

BACKGROUND

Topical anesthetics are important tools for many dermatologic procedures. The S-Caine Peel is composed of a 1:1 (w:w) eutectic mixture composed of lidocaine base 7%, USP, and tetracaine base 7%, USP. It is applied as a cream, dries on exposure to air, and forms a flexible membrane, which can be easily peeled off.

OBJECTIVE

To evaluate the effectiveness of the S-Caine Peel in providing clinically useful local dermal anesthesia for laser-assisted tattoo removal and to monitor the nature and frequency of adverse events associated with the safety of the S-Caine Peel.

METHODS

Thirty adult patients undergoing laser-assisted tattoo removal were enrolled in this multicentered, randomized, double-blind, placebo-controlled study. Each subject received both the S-Caine Peel and placebo simultaneously for 60 minutes. The primary efficacy parameter was a 100 mm visual analog scale (VAS) for patient self-assessment of pain. Secondary efficacy parameters included both the investigator's and an independent observer's evaluation of subject pain (4-point categorical scale: no pain through severe pain) and the patient's and the investigator's overall impression of the local anesthetic.

RESULTS

Mean VAS scores were 42 mm for the S-Caine Peel and 66 mm for placebo treatment sites (p=.001). Patients received adequate pain relief in 50% of S-Caine Peel sites versus 7% of placebo sites (p=.002). The percentage of those who would like to use the S-Caine Peel again were 43% for the S-Caine Peel compared with 7% for placebo (p=.005). Investigators' evaluations revealed that 70% of patients had less pain at S-Caine Peel treatment sites compared with 10% with less pain at placebo sites (p<.001), and 70% of the S-Caine Peel-treated sites achieved adequate anesthesia versus 10% of placebo sites (p<.001). The independent witness assessed less pain in 67% of S-Caine Peel-treated sites versus 10% of the placebo sites (p=.002). One occurrence of moderate to severe erythema was noted at both an S-Caine Peel and a placebo treatment site on removal of the S-Caine Peel after 60 minutes, which self-resolved quickly. There was no statistical difference between the two groups. Other side effects were limited to local mild, transient erythema at the application sites.

CONCLUSION

Administration of the S-Caine Peel for 60 minutes prior to laser-assisted tattoo removal was effective in significantly reducing pain levels associated with the procedure.

EMLA cream-induced irritant contact dermatitis

BACKGROUND

The Eutectic Mixture of Local Anesthetics (EMLA cream) is a topical anesthetic used for providing pain relief in patients undergoing superficial surgical procedures. Cutaneous side-effects have been reported rarely.

CASE REPORT

We present a case of irritant contact dermatitis induced by EMLA cream in a 6-year-old boy with Wiskott-Aldrich syndrome. Our patient showed clinically a well circumscribed patch corresponding to the site of application of the topical anesthetic. Histopathology showed confluent necrosis of keratinocytes in the upper epidermis, a mixed inflammatory infiltrate with priminent neutrophils in the upper dermis, and focal signs of interface changes including basal cell vacuolization and subepidermal cleft formation.

CONCLUSIONS

Graft-vs.-host-disease (GVHD), necrolytic migratory erythema, dermatitis enteropathica and pellagra should be considered in the histopathologic differential diagnosis of acute contact dermatitis caused by EMLA.

Topical anesthetics in dermatology

Topical anesthetics are valuable tools for the dermatologists. The purpose of this study is to educate dermatologists about the pharmacology and clinical applications of topical anesthetics. A review of the current topical anesthetics was conducted. Several topical anesthetics are available to provide safe and effective cutaneous analgesia. Patient care can be improved by reducing the discomfort of local procedures and by minimizing the side effects of the anesthetics.

The efficacy of EMLA versus ELA-Max for pain relief in medium-depth chemical peeling: a clinical and histopathologic evaluation

BACKGROUND

Medium-depth chemical peels are an effective and popular treatment for actinic damage, fine wrinkles, and pigmentary dyschromias. However, they are also uncomfortable. A previous attempt to study the effectiveness of a topical anesthetic gel in 35% trichloroacetic acid (TCA) peeling found a reduction in discomfort but an increased depth of penetration and delayed healing.

OBJECTIVE

To evaluate both the efficacy of two topical anesthetic agents in medium-depth combination peeling as well as the histologic result from chemical peeling combined with topical anesthesia.

METHOD

Seventy percent glycolic acid (GA) was applied to the entire face of 10 patients and diluted with water after 2 minutes. This was followed by the sequential application of EMLA cream (lidocaine 2.5% and prilocaine 2.5%), ELA-Max cream (lidocaine 4%), and placebo to selected areas on the face for 30 minutes without occlusion. These agents were then removed and 35% TCA was applied to the entire face. The level of discomfort felt by the patients during the TCA peel was recorded, clinical photographs were taken, and bilateral preauricular biopsies were performed at baseline, 48 hours, and 90 days postoperatively.

RESULTS

Clinically there was a statistically significant decrease in pain felt during the 70% GA-35% TCA peel with topical anesthesia when compared to the control. There was no statistically significant difference in efficacy between EMLA and ELA-Max. There was also no difference in either the clinical or the histopathologic appearance between the medium-depth peel combined with topical anesthesia and the medium-depth peel with control.

CONCLUSION

Both EMLA and ELA-Max decrease the discomfort felt during medium-depth combination chemical peeling without influencing either the clinical or the histopathologic result.