Objective:

To present a case of ischemic stroke associated with nitrous oxide abuse and demonstrate its multifaceted mechanism.

Background:

Recreational use of inhaled nitrous oxide (“whippets”) has been rising in younger populations. Unfortunately, many young adults using this substance do not know about the severe clinical manifestations that chronic use can lead to. 

Design/Methods:

NA

Results:

We report a case of a 36-year-old male with history notable for polysubstance use disorder in remission, using recreational nitrous oxide as a substitute, who presented with one month of progressive lower extremity weakness and paresthesia. Neurologic exam revealed a length-dependent polyneuropathy. Head and neck imaging showed a subocclusive thrombus in the right subclavian artery, proximal to the vertebral origin, as well as a small infarct in the right posterior inferior cerebellar artery (PICA) territory. Laboratory testing revealed macrocytosis, severe vitamin B12 deficiency, and elevated homocysteine. These findings highlight some of the complex neuropathic and vascular consequences that arise from nitrous oxide abuse. The patient was treated with oral anticoagulation and parenteral B12 supplementation. On three-month follow-up, CTA showed resolution of thrombus, there was normalization of B12 and homocysteine levels, and his polyneuropathy was clinically improved. 

Conclusions:

Nitrous oxide use can cause functional B12 deficiency leading to hyperhomocysteinemia, a hypercoagulable state, and subsequent ischemic stroke. Though many pathologic manifestations caused by vitamin B12 deficiency are reversible, its early recognition and treatment can prevent permanent complications. This is why it is crucial to educate the public (particularly high-risk populations) and increase awareness among clinicians on the potential irreversible consequences that nitrous oxide use can lead to.