PO009 Nitrous oxide induced myeloneuronopathy

Nitrous oxide (NO) is an increasingly used recreational drug amongst the young. Six patients presented to our unit with varying neurological presentations ranging from acute AIDP to a pure cord syndrome, mostly with a mixture of peripheral and central elements (myeloneuropathy). Some patients did not admit to taking it initially. Therefore a high index of clinical suspicion is needed. Most of the patients responded well to aggressive parenteral Vitamin B12 administration. This case series highlights the need to keep NO abuse in mind in younger patients who present with an acute cord syndrome or AIDP. Homocysteine and methylmalonic acid levels can be useful in suspected cases, even when abuse is denied by the patient.