Methamphetamine is the drug war's newest poster child for good reason: not only is it one of the most popular illicit drugs in the United States, it's also a notoriously hard habit to drop, and the lengthy periods of withdrawal and craving that repeated use creates may change the human brain in near-permanent ways. In a new study, researchers have identified the mechanisms behind meth addiction and the long-standing neurological damage it may cause.
Previous studies blamed meth's intense withdrawal symptoms on neurological changes similar to those seen in the brains of individuals suffering from chronic depression and anxiety disorders, and new research bears out this belief. Like most intoxicants, meth prompts an unusually heavy release of the pleasure-inducing neurotrasnmitter dopamine into the system, providing the physical and psychological peaks whose eventual valleys lead to a desire for more and greater stimulation: thus the addiction cycle. And the drug truly conditions the user - researchers at the University of Washington found that, in its absence, the brains of lab rats who'd been dosed only a few times lapsed into a depression that could only be relieved by reintroducing the drug into the system. This literal depression occured in the presynaptic terminals, or structures through which the transfer of neurotransmitters across a chemical synapse occurs. These synapses can only maintain their constantly heightened state of dopamine transmission for so long before they effectively collapse, unable to perform their standard functions, and this shutdown relieves the body of its ability to experience any kind of pleasure. An affected brain is left dull and unresponsive, and this result is the very opposite of that created by using the drug. Chronic meth users are prone to compulsive behavior and have been known to focus obsessively on certain stimuli, going without sleep for several days at a time as they descend into fits of psychosis.
The drug's withdrawal side-effects are every bit as epic. Researchers estimate that 10 days of meth use creates a period of depression lasting at least 4 months. And intense physical cravings persist for that entire period. This chemical condition, compounded over time, leads to the physical and psychological degeneration so common to chronic meth abuse. The mind and body essentially begin to decay and the brain is unable to return to its previously unaffected state. The persistence of meth addiction is far more understandable when viewed through this lens.
Perhaps the study's most unsettling finding was that total abstinence, even when maintained for the equivalent of one or more human years, did not reverse the damage caused by this initial exposure. The only way to reverse the depression of the affected brain was to supply it with more meth. If the patterns observed in these rats prove as close to those seen in long-term meth users as researchers suspect, their findings could have major implications on the future of related treatments. Unfortunately, this study also implies that a methadone-style regimen designed to gradually wean patients off the drug would probably not work for meth, because even small doses refresh the harm already done. The lasting damage to the brain's communicative functions, at least, could not be corrected with this method.
The only current treatment for methamphetamine addiction is behavioral intervention. We may, at some point in the wake of more studies like this one, gain the ability to chemically reverse the neurological changes so common to meth addiction. But for now such promising approaches are purely hypothetical. Still, if we can make addicts more fully aware of the long-lasting damage that meth wreaks on their brains and bodies, we may be able to scare more of them into toughing it out. Comorbid mental health conditions often require additional treatment for recovering addicts, but as this study makes clear, addicts must stay away from the drug altogether if they want to end its horrible influence. Absolute, permanent abstinence is the only way.
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