A man woke up unable to walk. It turned out vitamin B12 was inactivated in his body after he took laughing gas.

When Vito Oliveri, 34, and Emily Shuford, 30, first used nitrous oxide they felt instant euphoria.

Eight years after first using the drug, Oliveri got pins and needles and woke up unable to walk.

Experts are worried about nitrous oxide's potential harms amid the rise of super-size canisters.