In all forms, meth stimulates the central nervous system, with effects lasting anywhere from 4 hours to a few days. Meth use can not only modify behavior in an acute state, but after taking it for a long time, the drug literally changes the brain in fundamental and long-lasting ways. It kills by causing heart failure (myocardial infarction), brain damage, and stroke and it induces extreme, acute psychiatric and psychological symptoms that may lead to suicide or murder.
Some users often get the sensation that bugs are underneath their skin crawling around, which makes them pick and scratch.
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