Lidocaine is an amide local anesthetic and bupivacaine is an ester local anesthetic. The biggest difference between these two drugs is that the toxicity of bupivacaine to humans is exponentially higher compared to lidocaine, and in addition may lead to some increased allergies. Bupivacaine is most commonly used in dentistry, otolaryngology, and ophthalmology, mostly for anesthesia of these mucosal surfaces. Bupivacaine is a spray or aqueous agent that is sprayed or applied to the mucosal surfaces to produce anesthesia for examination and treatment, or for surgical treatment. Lidocaine is mainly used for local anesthesia or hemianesthesia of the human body, as well as limb and nerve block anesthesia.