The efficacy profile of lidocaine as a local anesthetic is characterized by a rapid onset of action and intermediate duration of efficacy. Therefore, lidocaine is suitable for infiltration, block, and surface anesthesia. Longer-acting substances such as bupivacaine are sometimes given preference for subdural and epidural anesthesias; lidocaine, though, has the advantage of a rapid onset of action.
Epinephrine (adrenaline) vasoconstricts arteries, reducing bleeding and also delays the resorption of lidocaine, almost doubling the duration of anaesthesia. For surface anesthesia, several available formulations can be used for endoscopies, before intubations, etc. Buffering the pH of lidocaine makes local freezing less painful.
Nov 2, 2018 - Lidocaine is a local anesthetic (numbing medication). It works by blocking nerve signals in your body. Lidocaine topical (for use on the skin) is used to reduce pain or discomfort caused by skin irritations such as sunburn, insect bites, poison ivy, poison oak, poison sumac, and minor cuts, scratches, or burns