International Academy of Cosmetic Dermatology
LEGAL CONSIDERATIONS IN THE APPLICATION OF TOPICAL LIDOCAINE
An important aspect of effective laser treatment for hair removal is effective pain control. While cooling tips provide a degree of analgesia, they are sometime inadequate to control pain. To provide analgesia for laser procedures, other agents are often used, in particular, topical lidocaine. Even though the lidocaine is applied to the skin, such a topical anesthetic can induce shock and rarely death  due to systemic absorption that leads to (1) methemoglobinemia, (2) cardiac arrest, or (3) idiosyncratic reaction.
Methemoglobinemia complicating topical lidocaine used during endoscopic procedures and before circumcisions in infants has resulted in loss of consciousness, coma, and even death.  Several cases where patients where topical lidocaine was applied over large areas with or with out occlusion has been reported.
In 2000, a 20-year-old Coast Guard cadet died due to an allergic reaction and cardiac arrest after EMLA® cream was applied to his back. A plastic surgeon in McLean, Virginia had applied a topical anesthetic to the back prior to planned laser hair removal His parents filed a wrongful death lawsuit and settled the case for $725,000.
Recently, I learned of a case involving the use of a topical compounded mixture of lidocaine and tetracaine applied to the legs under occlusion on a healthy 23-year-old women resulting in a respiratory arrest and ultimately death. The combination of a long and short agent that affects the heart when absorbed systemic can be dangerous.
I have not been able to identify any cases involving lidocaine 4% cream (LMX4®) or lidocaine 5% cream (LMX5®) that have resulted in death but this does not mean that LMX® is without side effects. The threshold for toxicity of “caine” type drugs is not clear. An article discussing the use of “caine” drugs in dentistry pointed out that adverse reactions to dental anesthetic might be due true allergy, psychogenic reaction (syncope), normal toxic overdose, or idiosyncratic toxic overdose. 
While the cases and facts that I have adduced do not mean that topical lidocaine should not be used to effect topical pain relief, they strongly suggest that topical lidocaine should be used with care and that its use on large areas (the back is 18% of body surface and each leg another 18%) should be approached with caution and a knowledge of potential side effects
. Lidocaine: Death following topical administration: case report. Drug Reactions 2000;1:9.
. Karim A, Ahmed S, Siddiqui R, Mattana J. Methemoglobinemia complicating topical lidocaine used during endoscopic procedures. Am J Med 2001;111:150-3.
. Levy SM, Baker KA. Considerations in differential diagnosis of adverse reactions to local anesthetic: report of case. J Amer Dental Assn (1939) 1986;113:271-3.
Noah Scheinfeld, MD, JD
New York, NY