A 19-year-old male undergraduate who was referred to our hospital in a wheelchair on March 31, 2017 because of inhaling nitrous oxide (“laughing gas”)... He experienced heavenly pleasure after inhalation, accompanied with fragmentation in his listening comprehension, suspicion and feelings that his family and friends were against him as well as feeling someone was talking about him when he was walking up the stairs. He had more nightmares and couldn’t distinguish between dreams and reality. ... With the use of nitrous oxide from morning to night, the patient became careless and lazy, with progressive emotional instability, erectile dysfunction, urinary frequency and urgency. ... After moving in with his parents, the patient no longer used nitrous oxide, but the symptoms of irritability, suspicion, idleness and weakness in his limbs still were present. ... He had illogical thinking, presented with suspicion, relational persecutory delusions, stable emotions, occasional negative ideation, diminished consciousness, as well as partial insight loss. ... The patient was from a good family, but he did not receive a lot of support for this issue. ... His psychiatric symptoms were manifested as paranoid delusion, hallucination and emotional instability. His neural symptoms were manifested as significantly decreased muscle strength...