Abstract
Nitrous oxide (N₂O), widely used as a medical anesthetic, has increasingly been misused recreationally, especially among young people, due to its accessibility and perceived safety. However, prolonged use and high doses can cause severe complications, particularly through functional vitamin B12 dysfunction. These complications include neurological impairments, hematologic abnormalities, and thromboembolic events, such as pulmonary embolism. We report the case of a 20-year-old male with a history of chronic nitrous oxide consumption who presented with extensive bilateral lower limb thrombosis, pulmonary embolism, and peripheral neuropathy. Imaging confirmed extensive iliofemoral thrombosis and bilateral pulmonary embolism. The patient was treated with anticoagulation, vitamin B12 supplementation, and other supportive measures. This case highlights the need to raise awareness about the risks of recreational nitrous oxide use and underscores the importance of timely intervention to prevent severe complications.