Benzocaine (topical)

Contraindications

• Hypersensitivity to the active ingredient or any of its excipients
• Hypersensitivity to para-aminobenzoic acid, parabens or paraphenylenediamine or to commercial hair dyes
• History of allergy to local anaesthetics (such as procaine, butacaine or any other 'caine' anaesthetics)
• Known or suspected methaemoglobinaemia
• Coadministration with sulphonamides
• Coadministration with cholinesterase inhibitors
• Application to large areas of skin, eczematous, sunburnt, infected or broken skin

Cautions

• Pregnancy
• Breastfeeding
• Complete heart block
• Application around mouth or eyes
• Application to extensive body area
• Conditions that facilitate inhalation

Pregnancy

• Caution 
• There are limited amounts of data from the use of benzocaine in pregnant women

Breastfeeding

• Caution; no information available
• There is insufficient information on the excretion of benzocaine metabolites in human milk

Renal impairment

• No dose adjustment recommended

Hepatic impairment

• No dose adjustment recommended

Elderly

• No dose adjustment recommended

Skin and Subcutaneous Tissue Disorders

• Contact dermatitis
• Pruritis
• Localized oedema
• Erythema
• Rash
• Urticaria 

Immune, Blood and Lymphatic System Disorders

• Hypersensitivity
• Methaemoglobinaemia

• Sulphonamides
• Cholinesterase inhibitors

By decreasing the neuronal membrane's permeability to sodium ions, benzocaine blocks the initiation and conduction of nerve impulses, thereby causing inhibition of depolarization which results in blockade of conduction.