A person doesn’t develop substance use disorder (SUD) or alcohol use disorder (AUD) all at once. It’s also not a matter of one bad decision or a simple lack of willpower. Instead, addiction builds over time through a series of shifts—in behavior, brain chemistry, and emotional dependence. To better understand how someone develops this brain disease, it helps to recognize the signs of addiction as a gradual deepening of dependency that unfolds in distinct, but often overlapping, stages.
1. How Substance Use Often Begins
Maybe it’s a teenager drinking at a party, a college student experimenting with pills to manage stress, or someone reaching for a drink after a difficult day. The reasons for drug or alcohol use vary—curiosity, social pressure, emotional escape—but the outcome is often similar: the brain experiences a surge of pleasure.
These early experiences with substances trigger the release of dopamine and other “feel-good” chemicals in the brain’s reward system. This region, particularly the basal ganglia, lights up in response to the substance, reinforcing the behavior and filing it away as something worth repeating.
In these early stages, the brain’s prefrontal cortex—the area responsible for judgment, decision-making, and impulse control—is still functioning well. The individual is generally able to weigh pros and cons and make rational choices about whether or not to continue using. But the seeds have been planted.
2. When Use Becomes Routine: The Habit Takes Hold
As the brain continues to associate substance use with relief or pleasure, behavior shifts from occasional to habitual. Someone might begin drinking more regularly after work, or using drugs as a coping tool during emotionally difficult times. What was once a choice starts to feel like a reflex.
This stage of addiction isn’t necessarily dramatic. An individual might still be functioning as before—going to work, seeing family and friends, managing responsibilities—but their relationship with the substance changes. Behind the scenes, brain chemistry is also altered:
- The reward system grows more sensitive to the substance and less responsive to natural pleasures, like hobbies, socializing, or food.
- At the same time, the prefrontal cortex loses its ability to regulate impulses effectively. Decision-making becomes more emotionally driven, and the ability to “just stop” starts to slip away.
If there are other potential addiction risk factors—such as a genetic predisposition to dependency, environmental triggers, unmanaged mental health conditions, or past or current trauma—but not enough protective factors, a person at this stage might think about and lean on substance use more often.
3. The Rise of Tolerance
Over time, regular substance use often leads to tolerance. The brain, in an effort to maintain balance, becomes less sensitive to the chemical effects of the substance. As a result, a person needs larger amounts—or stronger substances—to achieve the same effect. This escalation is particularly dangerous because it reinforces the behavior while increasing physical risk. What started as a glass of wine or a pill can quickly become several drinks or multiple doses just to feel okay.
With this increased tolerance, someone might believe that everyday life feels flat or harder to cope with if they don’t have the substance. Things that used to bring joy—music, exercise, relationships—lose their impact. The National Institute on Drug Abuse notes that they might also experience mood swings and physical discomfort if they’re not using more frequently. This is the beginning of AUD or SUD.
4. Addiction at Its Peak
Eventually, what started as a choice becomes a need, both physically and psychologically. The brain is now wired to expect the presence of the substance. Its absence triggers stress responses, largely due to changes in areas like the amygdala, which governs emotion and fear.
Without the substance, an individual might experience withdrawal symptoms such as:
- Intense cravings
- Anxiety and panic attacks
- Depression or hopelessness
- Fatigue or low energy
- Insomnia or disrupted sleep
- Sweating and chills
- Nausea and vomiting
- Muscle aches or body pain
- Headaches
- Tremors or shakiness
- Difficulty concentrating
- Increased heart rate or blood pressure
- Seizures or convulsions, especially with alcohol or benzodiazepine withdrawal
- Hallucinations
- Suicidal thoughts or behaviors
At this stage, attempts to quit often fail—not because someone doesn’t want to stop or have the willpower to do so, but because substances have rewired their reward system and dulled their natural coping abilities. Recovery for this chronic disease typically requires medical support, comprehensive treatment solutions, behavioral therapy, and long-term treatment strategies.
How Northern Path Can Help
At Northern Path Recovery Center in Fort Wayne, IN, our board-certified professionals provide a personalized treatment approach for AUD or SUD through evidence-based practices such as medically managed detoxification, trauma-informed care, holistic well-being techniques, and dedicated aftercare. Our goal is to prepare clients for long-term addiction recovery and to be with them every step of the way. If you or a loved one believes it’s time for healthier solutions, call our admissions team today.
