Background
Nitrous oxide (N₂O) is used in surgery and dentistry for its anesthetic and analgesic effects. However, neurological and psychiatric manifestations of N₂O abuse have been increasingly reported among Korean adults. The aim of this study was to demonstrate laboratory findings of N₂O abuse in Korean patients.
Methods
Patients diagnosed with N₂O-induced neuropathy or myelopathy from August 2018 to December 2019 were enrolled. Their clinical presentations and laboratory and imaging findings were analyzed.
Results
Sensory changes and limb weakness were present in nine of the enrolled patients. The laboratory findings revealed that seven patients had high homocysteine levels and five had high methylmalonic acid levels in their blood. Nerve conductions studies indicated that axonal neuropathy was present in four cases and longer F-wave and Hoffman’s-reflex latencies were present in two cases. Signal changes in cervical spine imaging occurred in five patients, while two had normal results.
Conclusions
Chronic N₂O abuse can cause neurological damage or psychiatric problems. Because N₂O is illegal for recreational use in Korea, patients tend to hide their history of use. Even though the spinal imaging results were normal, clinicians should consider the possibility of N₂O use, and further electrophysiological tests should be applied for precise evaluations.

Citations

• The prevalence, risks, and detection of driving under the influence of nitrous oxide
  Frederick R. J. Vinckenbosch, Dinesh Durán Jiménez, Hendrik Helmerhorst, Albert Dahan, Leon Aarts, Floris Bikker, Eef Theunissen, Johannes G. Ramaekers
  WIREs Forensic Science.2024;[Epub]     CrossRef
• Nitrous‐oxide‐induced polyneuropathy and subacute combined degeneration of the spine: clinical and diagnostic characteristics in 70 patients, with focus on electrodiagnostic studies
  L. T. Hassing, F. Y. Jiang, R. Zutt, S. Arends
  European Journal of Neurology.2024;[Epub]     CrossRef
• Severe Isolated Peripheral Polyneuropathy without Myelopathy after Nitrous Oxide Abuse: A Case Report
  Seung-Min Baek, Seungbok Lee, Yu-Mi Kim, Eun-Sil Kim
  Journal of Electrodiagnosis and Neuromuscular Dise.2022; 24(2): 50.     CrossRef

Guillain-Barre syndrome (GBS) is acute inflammatory demyelinating polyradiculoneuropathy, which is often related to post-infectious etiology. However, GBS has also been reported to be caused by non-infectious factors such as trauma. This report describes a rare case of post-traumatic GBS with dramatic response to immunoglobulin therapy. And here, we also discussed about the importance of differential diagnosis with critical illness polyneuropathy.

Citations

• MultiSpace Deep Fascial Infection in the Head and Neck Patient Complicated with Guillain-Barre Syndrome: Case Report with a Literature Review
  Fengxia Fan, Hongli Ni, Wanjie Luo, Qingchuan Yi
  Ear, Nose & Throat Journal.2025;[Epub]     CrossRef