Addiction

Addiction is a strong mental and physical dependence on a drug or other substance. Some substances that can lead to addiction are alcohol, drugs, some prescription medicines, and nicotine. Addiction is also sometimes called substance use disorder.

A person who has an addiction may have two or more of these symptoms:

  • Needing more of the drug or substance to get the same effect or getting less effect from the same amount over time (tolerance)
  • Having uncomfortable symptoms when they stop using the drug or substance or use less (withdrawal), or they are needing to use it to avoid withdrawal
  • Using more of the drug or substance or using it for a longer time than they ever meant to
  • Not being unable to cut down or control their use
  • Spending a lot of time getting or using the drug or substance or recovering from the effects
  • Not being able to do the things that are expected of them at work, at school, or at home
  • Continuing to use, even though the drug or substance use hurts their relationships
  • Having a strong need, or craving, for the drug or substance
  • Giving up important social activities or hobbies because of substance use
  • Using the drug or substance in situations where doing so is dangerous, such as driving
  • Using the drug or substance even though they know it's causing health problems

Current as of: May 1, 2026

Author: WebMD Ignite Staff

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