Why Is Addiction Permanent?
Addiction is permanent because the brain changes caused by excessive drug use can trigger irreversible genetic change.
This genetic change results from the way drug tolerance develops. Tolerance results from the brain’s defensive reaction to drug abuse. Drugs get people high by increasing the amount of dopamine in the brain’s Reward System, overstimulating it. If this happens often enough long enough, the brain learns to anticipate overstimulation and acts to counter it by making the Reward System less efficient. It does this by decreasing the number of receptors available for dopamine to dock with on the brain cells of the Reward System, limiting the amount of stimulation dopamine can cause.
Drug users counter tolerance by taking more drugs more often. This induces the brain to deepen tolerance by making the Reward System even less efficient, which requires users to take even more drugs to obtain the same high they used to get with less. A vicious downward-spiraling cycle develops as the brain tries to counteract drug abuse by gumming up the reward system ever further while the user compensates by taking more and more drugs. More drugs prompts further defensive brain changes, which in turn elicits increasing drug taking, accelerating the downward spiral. That’s a key reason addiction is a progressively-worsening disease.
At some point (it’s not known when yet), the brain interprets the overstimulation caused by escalating drug abuse as a permanent change in its environment. It reacts by making a permanent change in the genetic programming that engineers components of the Reward System. Once genetic change is triggered, it’s irreversible. That’s why addicts can never return to using drugs non-addictively. When they relapse, they quickly return to uncontrollable, obsessive use.
Since genetic change is permanent, it can be inherited. That’s why children of addicts have a higher risk of addiction. But not all addicts’ children become addicts themselves, indicating that there may be other biological and environmental factors involved. In 12-Step meetings one often hears second and third-generation addicts report that some of their siblings didn’t succumb to addiction (though their stories often indicate the majority did).
Addiction is a complex disease and there are many things addiction researchers still don’t know about how tolerance prompts genetic change. They believe many genes may be involved but have yet to identify them.
For more detail on why addiction is permanent click on Dopamine, Drugs and The Reward System.
Click here to return to the Questions About Addiction Menu.