Benzocaine is a local anaesthetic of the ester type, acting to produce reversible loss of sensation by preventing or diminishing the generation and transmission of sensory nerve impulses near the site of application. Depolarisation of the neuronal membrane and ion exchange are reversibly inhibited.
Benzocaine applied to the skin acts as a topical local anaesthetic, acting on nerve endings and receptors, temporarily reducing the itching and minor pain associated with various thermal, mechanical or chemical stimuli. The vanishing creme base also helps soothe, lubricate, and protect irritated skin.
When used as directed, some benzocaine applied topically may be absorbed through the skin and mucous membranes and is hydrolysed by esterases in the plasma and in the liver, but this should be of negligible consequence. Benzocaine has the quickest onset and shortest duration of action of the commonly used topical anaesthetics.
Preclinical Safety Data