Objective:

We present a unique case of nitrous oxide abuse presented with B12 deficiency symptoms and cerebral venous thrombosis.

Background:

Nitrous oxide is being used as a recreational drug. It's unknown side effects and low-price account for its rising popularity. In the paper, we discuss the link between nitrous oxide, vitamin B12 deficiency, and the development of cerebral venous thrombosis. 

Design/Methods:

A 33-year-old female, with a past medical history of anxiety, presented to the emergency department with a five-day history of BLE weakness, generalized numbness, and confusion. The patient appeared lethargic, disoriented, and confused. Gait evaluation showed sensory ataxia with a positive Romberg sign. No other neurological deficits were elicited. Patient denied usage of drugs or alcohol. A head CT showed a possible thrombus in the left transverse and sigmoid sinuses. This was confirmed by a computed tomography angiography (CTA) of the head and neck. Lab results showed elevated homocysteine and methylmalonic acid levels with decreased B12. Upon further discussion with the patient, she disclosed the use of Nitrous Oxide recreationally for about six months. Treatment included IM B12 1,000 mcg daily for 4 weeks, then monthly until future follow up. Patient was advised to avoid further use of Nitrous oxide. 

Results:

Chronic Nitrous oxide abuse can present as cerebral venous thrombosis (CVT). Though unusual, it needs to be included among possible complications/ presentations. 

Conclusions:

We recommend conducting an extensive workup on CVT, which includes homocysteine and B12 levels.