When Does Drug Use Become an Addiction?

Drug addiction is a complex and chronic brain disease. People who have a drug addiction experience compulsive, sometimes uncontrollable, craving for their drug of choice. Typically, they will continue to seek and use drugs in spite of experiencing extremely negative consequences as a result of using.

Characteristics of Addiction

According to the National Institute on Drug Abuse (NIDA), addiction is a chronic, relapsing disorder characterized by:

• Compulsive drug-seeking
• Continued use despite harmful consequences
• Long-lasting changes in the brain

NIDA also notes that addiction is both a mental illness and a complex brain disorder.

Behavioral Manifestations of Addiction

When friends and family members are dealing with a loved one who is addicted, it is usually the outward behaviors of the person that are the obvious symptoms of addiction.

Those behaviors are primarily centered around the addict's impaired control:

• The excessive frequency of drug use in spite of attempts to control
• Increased time using or recovering from drug effects
• Continued use in spite of persistent problems
• A narrowing of focus on rewards linked to addiction
• An inability to take steps to address the problems

The Inability to Abstain

Research has shown that prolonged drug use causes a chemical change in the brain of the addict that alters the brain's reward system that prompts compulsive drug seeking in the face of growing negative consequences.

This state of addiction, when the activity continues in spite of negative consequences and despite the fact it is no longer rewarding, is termed by addiction experts the "pathological pursuit of rewards." It is the result of chemical changes in the reward circuitry of the brain.

How Addiction Gets Started

The reason that people engage in activity that can become addictive in the first place is to experiment, because of the social environment, or achieve a feeling of euphoria or to relieve an emotional state of dysphoria.

Genetic Factors

Addiction also has a genetic component that may make some people more susceptible to becoming addicted to drugs. Some people have described feeling addicted from the first time they use a substance. Researchers have found that the heritability of addictions is around 40—60% and that genetics "provide pre-existing vulnerabilities to addiction [and] increased susceptibility to environmental risk factors." 

Changes in the Brain

A high is the result of increased dopamine and opioid peptide activity in the brain's reward circuits. But after the high they experience, there is a neurochemical rebound which causes the reward function of the brain to drop below the original normal level. When the activity is repeated, the same level of euphoria or relief is not achieved. Simply put, the person never really gets as high as they did that first time.

Lower Highs and Lower Lows

Added to the fact that the addicted person develops a tolerance to the high—requiring more to try to achieve the same level of euphoria—is the fact that the person does not develop a tolerance to the emotional low they feel afterward. Rather than return to "normal," the person reverts to a deeper state of dysphoria.

When becoming addicted, the person increases the amount of drugs, alcohol, or the frequency of the addictive behaviors in an effort to get back to that initial euphoric state. But the person ends up experiencing a deeper and deeper low as the brain's reward circuitry reacts to the cycle of intoxication and withdrawal.

No Longer a Function of Choice

To put it another way, the addicted person finds himself compelled—despite his own intentions to stop—to repeat behaviors that are no longer rewarding to try to escape an overwhelming feeling of being ill at ease but find no relief.

According to ASAM, at this point addiction is no longer solely a function of choice. Consequently, the state of addiction is a miserable place to be, for the addict and for those around him.

Chronic Disease and Relapses

For many addicts, addiction can become a chronic illness, meaning that they can have relapses similar to relapses that can happen with other chronic diseases—such as diabetes, asthma, and hypertension—when patients fail to comply with their treatment. These relapses can occur even after long periods of abstinence. The addict can take action to enter remission again. But he remains at risk of another relapse. The ASAM notes "Without treatment or engagement in recovery activities, addiction is progressive and can result in disability or premature death."