Methamphetamine, as a stimulant drug, can produce depleting damage to the nervous system, leading directly to the depleting death of nerve cells, with clinical manifestations ranging from a light state of anxiety, to a medium state of schizophrenia with hallucinations and delusions, to a heavy state of psychosis plus dementia. Brain atrophy can be seen on MRI of the head. It can also lead to cerebral vasospasm and cardiovascular spasm, insufficient blood supply to the brain and heart, clinical manifestations of light headache (can become episodic frying pain and chronic boring pain), serious brain ischemic foci, hemorrhage points, and also sudden death due to massive smoking leading to myocardial infarction. Please stay away from drugs.