Dependence is when a person’s body has begun to develop a tolerance to a drug, and more and more of that drug is needed to get the same effect. If the drug were to be stopped, the body would begin to go through withdrawal. This can happen even if the drug is taken as directed by a doctor.
Addiction, however, is when an individual becomes physically unable to stop taking a drug even though that drug use is causing negative consequences. It is important to note that opioid addiction is not a moral failing, but a chronic disease. Just as you would do for a heart condition or cancer, finding the right mix of treatment options and wrap-around services is crucial.
Dependence will always happen before addiction, but not everyone who is dependent on a drug will develop an addiction. The National Institute on Drug Abuse’s website has much more detail on this topic.