Local Anaesthesia, strictly speaking, means putting local anesthetic ("freezing") around the affected area to make it pain free. Technically speaking, local anesthetics are drugs that block sensory and motor nerve conduction to produce temporary loss of sensation without loss of consciousness. The loss of sensation is restricted to the area where the injection is applied. The other areas of the body are not anaesthetized. Local anesthetics are readily absorbed through mucous membranes and damaged skin. For certain procedures, adding adrenaline prolongs the duration of action.
Local anaesthetics can be applied close to the nerve of any part of the body,e.g,a finger, an eyelid, the foot or a tooth that require an operation without other areas getting anaesthetized. It can be applied within the mouth, nose or throat or any area lined by mucous membrane in the form of a spray, or gel or by means of an injection and operations done on the affected part with the patient remaining conscious.