Nitrous oxide, commonly known as "laughing gas," is a widely known recreational drug, especially among young people. Reasons for its popularity are its low price and easy availability online. However, long-term use can lead to serious neurological problems rooted in functional vitamin B12 deficiency. Key symptoms include spinal cord damage, nerve damage and behavioral abnormalities. If a patient develops symptoms suggestive of vitamin B12 deficiency, it is recommended that a medical professional inquire about the patient's use of nitrous oxide.
Nitrous oxide, commonly known as "laughing gas," is not only a popular recreational drug, especially among young people, but it is also a frequently used anesthetic in pediatric and dental procedures. Because it's cheap and easily available online, many people use it to get a quick high. In the 2021 Global Drug Survey, 10% of respondents and 15% of Canadian respondents reported using the drug in the past year.
"Nitrous oxide's low cost and easy availability have made it a popular recreational drug, especially among young people," wrote Dr. Cyrille DeHalleux, an internal medicine specialist in the Department of Clinical Pharmacology and Toxicology at the University of Toronto and a physician, critical care and resident physician at the Hospital for Sick Children (SickKids) in Toronto, Ontario.
Long-term use of nitrous oxide can lead to functional vitamin B12 deficiency, which can cause long-term health effects, especially neurological consequences. The three most common manifestations of toxicity are spinal cord injury (myelopathy), nerve damage affecting strength and sensation (neuropathy), and behavioral abnormalities (encephalopathy). Treatment includes discontinuing use of the substance and supplementing with vitamin B12 and methionine.
The authors concluded: "Clinicians should inquire about the use of laughing gas in patients with unexplained vitamin B12 deficiency or other corresponding neurological symptoms."