Drug Addiction: Symptoms & Signs

Medically Reviewed on 9/15/2020

Drug addiction is grouped with drug use as substance or drug use disorder, which is a condition characterized by a self-destructive pattern of using a substance that leads to significant problems and distress. Drug use disorder can also include tolerance to or withdrawal from the substance.

Signs and symptoms of drug addiction vary depending on the type of substance being used and the individual who is affected. Symptoms and signs associated with drug addiction can include

  • mood changes,
  • bloodshot eyes,
  • preoccupation with acquiring or using the drug,
  • reckless behavior,
  • stealing to pay for drugs,
  • loss of interest in everyday activities,
  • hiding drug use,
  • difficulty getting along with others, and
  • sleeping too much or too little.

Children or adolescents may begin to associate with a different group of friends. Other symptoms can include

  • withdrawal symptoms when the drug is not available,
  • change in appearance and hygiene,
  • personality changes,
  • bloody nose,
  • tremors,
  • shakes, and
  • change in daily routine.

Cause of drug addiction

The exact cause of drug addiction is likely related to a combination of genetic factors and environmental influences.

Other drug addiction symptoms and signs

  • Bloodshot Eyes
  • Bloody Nose
  • Change in Appearance and Hygiene
  • Change in Daily Routine
  • Difficulty Getting Along With Others
  • Hiding Drug Use
  • Loss of Interest in Everyday Activities
  • Mood Changes
  • Personality Changes
  • Preoccupation With Acquiring or Using the Drug
  • Reckless Behavior
  • Shakes
  • Sleeping Too Much or Too Little
  • Stealing to Pay for Drugs
  • Tremors
  • Withdrawal Symptoms When the Drug Is Not Available


Prescription Drug Abuse: Addiction, Health Risks, and Treatments See Slideshow

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Jameson, J. Larry, et al. Harrison's Principles of Internal Medicine, 20th Ed. New York: McGraw-Hill Education, 2018.