The Difference Between Opioid Addiction and Physical Dependence

Opioids are a complicated class of medications that are often associated with addiction. However, not every person who takes an opioid will become addicted. This page will discuss the differences between physical dependence and addiction, as well as criteria for defining the different forms of addiction.

See Opioid Medication Potential Risks and Complications


Physical dependence and opioid addiction are not the same

People often confuse physical dependence on opioids and opioid addiction; however, there are important distinctions between the two conditions.

  • Physical dependence is a common physiologic response seen with chronic opioid use when the opioid dose is rapidly decreased or discontinued leading to withdrawal. Common signs and symptoms of withdrawal include diarrhea, increased pulse, sweating, muscle aches, increased pain, restlessness and anxiety.
  • Addiction involves genetic, environmental, and neurological factors and results in unrestrained and compulsive use of a drug.1 Generally, addiction is present when a back pain patient continues to use a drug despite no longer needing it, uses a drug for recreational purposes, or continues to use it despite negative consequences.

Recent criteria has further clarified the definition of addiction

To better treat people the American Psychiatric Association (ASA) has further specified the different types of addiction.

  • Substance use disorder (SUD). Defined as mild, moderate, or severe based on a number of diagnostic criteria met by an individual. Substance use disorders occur when the recurrent use of alcohol and/or drugs causes clinically and functionally significant impairment. This includes health problems, disability, and the failure to meet major responsibilities at work, school, or home. Common substance use disorders include alcohol, tobacco, and other drugs.
  • Opioid use disorder (OUD). Opioid use disorder combines both opioid dependence and opioid abuse. It has similar symptoms to substance use disorder and diagnosis will be specific to the drug being abused, such as heroin or prescription opioids. The ASA explicitly states that opioid use disorder is not applicable to those who take opioids correctly and under medical supervision.

Addiction will look different in every individual. Although there can be outward signs and symptoms, many people can go about their day-to-day work and activities while still struggling with addiction.


  • 1.Morgan MM, Christie MJ. Analysis of opioid efficacy, tolerance, addiction and dependence from cell culture to human. British Journal of Pharmacology. 2011;164(4):1322-1334. doi:10.1111/j.1476-5381.2011.01335.x.