Updated April 28, 2015.

Definition: A multifaceted chronic disease in which a person cannot control himself around a drug or medication. An addicted person will crave the drug, not for pain relief, but for other reasons. He is likely to take the drug compulsively, and may even continue to use it when it is obviously causing him harm.

According to the University of Iowa Gerontological Nursing Interventions Research Center, between 3% to 16% of people in the United States have problems with addiction.