"Leave No One Behind"

Substance Use Disorders

When thinking of substance use disorders, it is helpful to view the levels of severity in four ways:

  • Experimentation
  • Social Use
  • Abuse
  • Physical Dependence

According to the American Society of Addiction Medicine addiction is a primary, chronic relapsing disease of our brain’s reward, motivation, memory and related circuitry.


Dysfunction in these circuits leads to biological, psychological, social and spiritual changes. Individuals with severe substance use disorders often lose their families, friendships, jobs, home, health and freedom because of their continued use of substances in spite of the negative consequences resulting from this behavior.
The way we learn to survive is based on a reward system. When we do something that aids in our survival, like eating or exercising, our brain’s limbic system rewards us for this behavior by releasing dopamine, a chemical that makes us feel good. Since we like the way we feel, we learn to repeat the behavior.

Drugs can cause the brain to release up to 10 times the amount of dopamine our brain normally releases giving the user a sense of a “rush” or “high.”

Because of this release and its impact on the brain’s reward center, users learn very quickly to continue use the substance.

They learn this in the same way they learn to eat or exercise, but even faster and with more intensity, since the release of dopamine is so much larger.

Since the amount of dopamine released is abnormal, the brain struggles to regain its normal chemical balance after a substance wears off.

This produces a hangover, or withdrawal, from a substance, which can manifest in physical pain, depression and even dangerous behavior.

Over time, prolonged use of a substance results in a decrease in the brains natural production of dopamine, creating further withdrawal, leading to a physical dependency — the addict needs to use more of the substance in order to feel normal, creating a vicious cycle – often resulting in destruction and even death.

Disrupting this cycle often requires rehabilitation and TIME to allow the brain to return to a “normal” state allowing the person to relearn how to function on a daily basis without relying on addictive substances.

Regardless of the reasons a person starts using, for some, an invisible line is crossed and the substance use moves from a recreational activity to a compulsive and destructive force in their life. Abnormalities in the brain of addicts create a feeling of need or craving that addicts know is irrational but cannot prevent on their own.

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