Opioid Addiction

Addiction is a neurobiological condition that results when a person ingests a substance or engages in an activity which exerts a powerful influence on the brain that manifests in three distinct ways: craving for the object of addiction, loss of control over its use, and continuing involvement with it despite adverse consequences.  Addiction is a chronic, relapsing brain disease characterized by compulsive use despite harmful consequences.  The process of addiction causes dysfunctional learning and memory and maladaptive behavioral patterns which include:

  • Impaired decision‐making, loss of control
  • Altered neurobiology: relapse risk even after extended periods of abstinence

Addiction is a type of disability, like any other physical or cognitive impairment. However, with the proper treatment, many individuals can overcome their addiction.  Recovering addicts are a protected class under the Americans with Disabilities Act (“ADA”).

Addiction and chemical dependency are not the same. Dependency is a normal physiological response to the repeated use of a substance.  Addiction is characterized by a loss of control, where one compulsively uses a substance despite life-threatening consequences.


Drug abuse costs the United States economy hundreds of billions of dollars in increased health care costs, crime and lost productivity.  Illicit drug use alone accounts for nearly $200 billion in health care, productivity loss, crime, incarceration and drug enforcement.

The economic burden in the United States for addiction is twice that of any other disease affecting the brain, including Parkinson’s and Alzheimer’ Disease, as well as all the others.


The brain registers all pleasures in the same way. It does not matter whether they originate from a psychoactive drug, a monetary reward, an exhilarating experience, or a satisfying meal. In the brain, pleasure has a distinct signature: the release of the neurotransmitter dopamine in the nucleus accumbens –a cluster of nerve cells lying underneath the cerebral cortex.

Dopamine release in the nucleus accumbens is so consistently tied with pleasure that neuroscientists refer to the region as the brain’s reward center.

All abused drugs cause a particularly powerful surge of dopamine in the nucleus accumbens. Addictive drugs provide a shortcut to the brain’s reward system by flooding the nucleus accumbens with dopamine.


Opiates are a group of drugs which are used medically to relieve pain, but also have a high potential for abuse. Some opiates come from a resin taken from the seed pod of the Asian poppy plant. This group of drugs includes opium, morphine, heroin, and codeine. Other opiates are synthesized or manufactured. There are a number of synthetic opiates which are used as painkillers, such as methadone, which is often prescribed for heroin and opiate addiction. Collectively, opiates and synthetic opiates are called opioids.

Opiates resemble natural chemicals in the body that bind to sites called opiate receptors. When administered, opioids attach to the abovementioned receptors. They then activate the receptors since their chemical structure mimics that of the natural neurotransmitter. This similarity in structure tricks receptors and allows the drugs to lock onto and activate the nerve cells.

Opioids target the brain’s reward system by flooding the circuit with dopamine. Dopamine is a neurotransmitter present in regions of the brain that regulate movement, emotion, cognition, motivation, and feelings of pleasure. The overstimulation of this system, which rewards our natural behaviors, produces the euphoric effects.


Brains are wired to ensure that people will repeat life-sustaining activities by associating those activities with pleasure or reward. Whenever this reward circuit is activated, the brain notes the responsible activity, and teaches the individual to subconsciously continue the activity again and again. Because drugs of abuse stimulate the same circuit, individuals learn to abuse drugs in the same way.

Long-term opiate use changes the way nerve cells work in the brain. The nerve cells become accustomed to having opiates around that when they are taken away suddenly, the individual may experience a wide range of symptoms in the brain and body. These are known as withdrawal symptoms. The symptoms and severity of opiate withdrawals is dependent on age, usage amount and length of usage. Accordingly, individuals who have a longer history of opiate abuse will experience longer, more difficult withdrawal.
According to the CDC, there are enough prescription painkillers prescribed a year to medicate every American adult around-the-clock for an entire month.


When drugs are used repeatedly over time, tolerance may develop. Tolerance occurs when the individual no longer responds to the drug in the way that they initially responded. In other words, it takes a higher dose of the drug to achieve the same level of response originally achieved.

Dependence develops when the neurons adapt to the repeated drug exposure and only function normally in the presence of the drug. When the drug is withdrawn, several physiologic reactions occur. These reactions may range from mild to life threatening depending on the substance. This reaction is known as the withdrawal syndrome. The symptoms of withdrawal include restlessness, muscle and bone pain, insomnia, diarrhea and vomiting, among others. Users also experience severe craving for the drug during withdrawal, which can precipitate continued abuse or relapse