With the use of nitrous oxide increasing, overuse and excessive exposure to this gas are also more prevalent. Neuropathy, expressed as amnesia, aphasia or weakness, numbness, and incoordination affecting all extremities, is the common result of frequent overexposure. For optimal dental treatment, it is recommended that both patient and dentist be aware that nitrous oxide can be an exogenous toxin, damaging to neuronal structures, if used in excess.