Topical Liposomal Lidocaine Formulations
LMX-4 is an OTC topical liposomal formulation of 4% lidocaine that was previously known as ELA-Max. It is rapidly absorbed through the skin and within 20 to 30 minutes produces an anesthetic effect that is sustained for up to 1 hour after application. LMX-4 is FDA-approved for the temporary relief of pain and pruritus associated with minor burns, cuts, and insect bites. The area of LMX-4 application should be no larger than 100 cm2 in children weighing ≤ 10 kg or between 10 kg and 20 kg for each use, because the amount of absorption depends upon the duration and surface area of the application.
When utilized in a clinical setting, LMX-4 was as effective as EMLA for alleviating pain from venipuncture and for reducing distress scores on an observer-rated behavioral scale. In children undergoing peripheral IV catheter insertion, LMX-4 was similar to buffered lidocaine for reducing pain and anxiety as rated by the patient, a parent, and a blinded observer. Furthermore, LMX-4 produced anesthesia within 30 minutes without the need for occlusive dressing, compared with 60 minutes for EMLA and its dressing.[9,10] Unlike EMLA, LMX-4 has not been found to induce methemoglobinemia and produces only minor local effects, such as blanching and erythema. In summary, LMX-4 has a faster onset of anesthesia and a more favorable adverse-effect profile than EMLA, and needs no prescription.
US Pharmacist. 2009;34(3):HS-4- HS-7. © 2009 Jobson Publishing
Cite this: Topical Anesthesia Use in Children - Medscape - Mar 01, 2009.