Tests at Medlatec Hospital in Ho Chi Minh City showed that his blood vitamin B12 levels were below normal.
Nerve conduction studies revealed signs of nerve damage in all four limbs, and doctors suspect acute myelin damage (nerve fiber sheath).
MRI images showed damage to the posterior column of the cervical spinal cord, extending from the second to the sixth cervical vertebra—typical damage often found in individuals who abuse nitrous oxide (N2O), also known as laughing gas, for extended periods, according to Hoang Anh Tuan, a neurology specialist at the hospital.
Tuan said prolonged exposure to N2O gas causes the body to deactivate vitamin B12, leading to spinal cord damage. Early signs often include numbness in the hands and feet.
If not detected in time, severe nerve damage can result in slow or no recovery, but since this patient was diagnosed early the prognosis for recovery is good if the treatment plan is strictly followed, he added.
The patient is undergoing outpatient treatment and will have regular follow-up visits to monitor progress, with MRI scans after three to six months to assess recovery of the cervical spinal cord damage.
Laughing gas is a colorless, odorless and tasteless compound.
Inhaling it directly affects the nervous system, causing euphoria, uncontrollable laughter and hallucinations, and makes the surroundings appear more colorful and vivid.
According to the Ministry of Health, the gas is typically used in a controlled manner as anesthesia in medicine and in industry for producing solar panels and increasing engine power.
But its misuse can have serious consequences for both physical and mental health.
Long-term abuse even at low doses can lead to nerve damage with symptoms such as seizures, numbness, paralysis, behavioral disorders, delusions, and hallucinations.
From Jan. 1 this year, laughing gas, shisha and e-cigarettes are banned substances in Vietnam.
Those who use or sell them face administrative or criminal penalties depending on the severity of the violation.