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Mental Health Center

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'Speed' May Cause Long-Term Damage to the Brain


Methamphetamine damage may not occur in patients who receive the drug in the small doses used to treat hyperactivity disorders in children or sleep disorders in adults. This is because lower doses of the drug may have an opposite effect than those seen with the large doses taken for recreational effects.

Rat studies by neurobiologist Wayne A. Cass, PhD, at the University of Kentucky in Lexington, show that methamphetamine does not necessarily kill brain cells, but instead damages them so that they stop working. Recent studies show that the rats' damaged cells can get better over time, and the rats eventually recover from toxic doses of methamphetamine.

In an interview with WebMD, Cass says that his rat model may not duplicate the effects of long-term methamphetamine use in humans, as the drug damages the rat brain after only one day of heavy exposure. Even so, his findings are not good news for former users of the drug. "Even though it took the rats only a year to recover, that is a third of their life," Cass points out. "Even if this recovery happens in humans it could take a long time, and whether humans could recover as well as rats is unknown."

Vital Information:

  • Methamphetamine is an illegal, recreational drug also known as meth, speed, crank, crystal, glass, chalk, or ice.
  • Researchers have found that former meth users experience long-term brain damage, and it is unknown whether the damage can ever be reversed.
  • The finding may explain why meth users can have long-lasting behavioral problems, such as violence, psychosis, and personality defects, for years after the last time they used the drug.
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