People with addictions (sometimes derogatorily labelled as “addicts”) may sometimes be thought of as having weak characters. But scientific evidence tells us that the roots of addiction are far deeper than simple human willpower. Whether the dependence is on alcohol, prescription medications, or other drugs, the misuse or overuse of any substance can become a chronic, relapsing medical condition. These conditions are associated with compulsive substance-seeking behaviour and use, even in the face of, often profound, negative life consequences. Simply speaking, addiction is a disease or medical condition—and those with the disease are often unable to break destructive behaviours without the help of others.
A Brain Disease
Addictive substances affect the brain’s reward and memory systems by stimulating the release of many chemicals in the brain, one of the most important of which is called dopamine. Overstimulation of dopamine can cause feelings of pleasure and euphoria. Brain imaging shows that long-term substance use can create physical changes in the brain in areas that control a person’s memory, behaviour and decision-making abilities. It is believed that these changes contribute to a number of complex processes that make it extremely difficult for a person to control compulsive behaviours. It’s as if brain connections get rewired over time with the use of the substance.
Defining Addiction, Dependence, and Abuse
You may have heard many different terms to describe substance use disorders: addiction, abuse, and dependence.
- Addiction is a broad term describing compulsive and repeated substance use despite harmful consequences
- Substance abuse refers to the harmful use of a substance such as alcohol and drugs (prescription medication or illicit substance)
- Substance dependence occurs when a person becomes dependent on the substance, needs larger amounts of it to get the same effect (also known as tolerance), and experiences withdrawal symptoms when stopping the use of the drug
The Diagnostic and Statistical Manual of Mental Disorder (DSM) is a reference book that lists the key signs and symptoms of mental illnesses. This manual refers to the spectrum of addictive illnesses as “substance use disorders” (e.g., alcohol use disorder, stimulant use disorder, opioid use disorder). Each substance use disorder can be measured as mild, moderate, or severe based on severity of the illness and how much the substance use disrupts the sufferer’s life.
What Causes a Person to Abuse Drugs or Alcohol?
The cause of substance use disorders is not clear. The conditions are known to run in families; however, while there are genetic risk factors, there is no one specific gene that has been identified as the cause. There are other known risk factors, including:
- Abuse, neglect, or other traumatic experiences in childhood
- Mental illness, such as depression or anxiety
- Lack of socialization during childhood
- Exposure to substances through peers
- Lack of support, or coping skills
When to Get Medical Care
Even though people with these disorders may be involved with different substances, the symptoms of the condition are similar. Common signs of a substance use disorder include:
- Neglecting responsibilities, such as at work, school, or home
- Getting in trouble with the law, such as driving while intoxicated or high
- Engaging in risky behaviour, such as using dirty needles or having unprotected sex
- Avoiding friends and family in order to use the substance
- Having feelings of hopelessness or depression, or having suicidal thoughts
If you or a loved one may have a substance use problem, there is medical help available. Treatments for addiction, which include medication and psychological therapy, have been very successful for many people. There are also rehabilitation facilities, counselling, and support groups that offer important resources. Keep in mind that every person’s recovery is different, in that what might work for one may not work for another. Work with a professional, such as a doctor or other healthcare provider, who is trained in substance use disorders, to find out what might work best for you.
Long-term recovery—that is, abstaining from using a substance and managing potential relapses—is a lifelong commitment but within reach. The first step in the journey to recovery is to seek help.
Daniel R. Karlin, MD, MA is a practicing board-certified psychiatrist, and a Director in the Neuroscience Research Unit at Pfizer.