Poisoning associated with inappropriate use of a eutectic mixture of lidocaine and prilocaine before laser-assisted hair removal: about 3 cases.

BACKGROUND: Eutectic mixtures of lidocaine and prilocaine are used during painful dermatological procedures. Poisoning is rarely reported in adults.

MATERIAL AND METHOD: We report three cases of women who experienced lidocaine and prilocaine poisoning after laser-assisted hair removal. Plasma levels of local anesthetics were assayed by a fully validated liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) method.

CASE REPORTS: The rules of application of the anesthetic cream were observed apart from the maximum dose and/or maximum surface area. One patient applied a higher dose than the maximum recommended dose (140 instead of 60 g) and all patients failed to comply with the maximum recommended surface area (600 cm2 ). The patients presented an unusual clinical pattern as compared with other local anesthetics overdose: signs of cardiac toxicity with no ECG changes or arrhythmia, neurological toxicity without seizures or coma, and methemoglobinemia.

DISCUSSION: Health authorities should publish explicit recommendations targeting users and prescribers with particular emphasis on the maximal surface area of application.