[Nitrous oxide-induced polyneuropathy].

Nitrous oxide, laughing gas, is used as a party drug to achieve a euphoric effect. It has been gaining popularity in recent years and is considered a relatively innocent substance. Nitrous oxide is known to cause subacute degeneration of the spinal cord by inactivation of active vitamin B12. Vitamin B12 plays an essential role in the synthesis of myelin. Hence, vitamin B12 deficiency can lead to degeneration of the dorsal and lateral columns of the spinal cord. Polyneuropathy is a less known complication. We present a 17-year-old woman and a 19-year-old man with subacute axonal polyneuropathy caused by laughing gas abuse. Abstinence of laughing gas and treatment with intramuscular and oral vitamin B12 suppletion respectively have led to improvement of their symptoms. Our cases demonstrate a less-known but treatable complication of laughing gas.