What is the treatment for chronic toxicity from nitrous oxide abuse?
High dose intramuscular vitamin B12 supplementation. A typical regimen is 1000 mcg IM daily for 14 days, followed by 1000 mcg IM weekly for four weeks, and then extended to monthly. Cyanocobalamin has generally been favored for its stability over other cobalamin forms. Because it has poor oral and intravenous bioavailability, intramuscular (IM) administration is preferred Permanent cessation of nitrous oxide is essential. In the cited reference, all patients had continued activation of B12 given persistent nitrous oxide abuse and experienced progressive neurologic deficits. Other treatments may include methylcobalamin, methionine, and folate, however no standardized regimen for nitrous oxide toxicity exists.
Courtney Temple & B. Zane Horowitz (2022) Nitrous oxide abuse induced subacute combined degeneration despite patient initiated B12 supplementation, Clinical Toxicology, 60:7, 872-875, DOI: 10.1080/15563650.2022.2046772