Education on Substance Use

Substance Use Disorders

A substance use disorder (SUD) is a mental disorder that affects a person’s brain and behavior, leading to a person’s inability to control their use of substances. The recurrent use of alcohol and/or drugs causes clinically significant impairment, including health problems, disability, and failure to meet major responsibilities at work, school, or home.

Symptoms can range from moderate to severe, with addiction being the most severe form. The disorder affects an individual’s brain and behavior, causing them to not have control over their use of substances such as drugs, alcohol, or medications. It is often progressive, resulting in greater impairment over time.

The coexistence of mental health and substance use disorders is referred to as co-occurring disorders. About half of people who experience a SUD will also experience a co-occurring mental disorder and vice versa.

Substance use disorders affect people from all walks of life and all age groups. Building understanding and connecting those struggling to resources is key in promoting and supporting recovery.

Warning Signs & Symptoms 

One of the best ways to support the people you care about is knowing the warning signs of substance use disorders.  

Physical Warning Signs 

  • Bloodshot eyes, pupils larger or smaller than usual
  • Changes in appetite or sleep patterns
  • Deterioration of physical appearance and/or personal grooming habits
  • Runny nose or sniffling
  • Sudden weight loss or gain
  • Tremors, slurred speech, or impaired coordination
  • Usual odors on body, breath, or clothing

Behavioral Signs 

  • Difficulties in one’s relationships
  • Engaging in secretive or suspicious behaviors
  • New or frequent legal trouble
  • Neglecting responsibilities at work, school, or home
  • Sudden change in friends, favorite hangouts, and hobbies
  • Unexplained need for money or new/increased financial problems
  • Using drugs under dangerous conditions (driving while using, using dirty needles, having unprotected sex)
  • Increased drug tolerance (the need to use more of a drug to experience the same effects that used to be achieved with smaller amounts)
  • Misusing drugs to avoid or relieve withdrawal symptoms (nausea, restlessness, insomnia, depression, sweating, shaking, anxiety)
  • Loss of control over drug use (using more than intended, unable to stop)
  • Life revolves around drug use (always thinking of using, figuring out how to get more, or recovering from use)
  • Abandoning enjoyable activities to use drugs
  • Continuing to use regardless of negative consequences

Psychological Signs 

  • Appearing fearful, anxious, or paranoid with no reason
  • Lack of motivation
  • Appearing tired or “spaced out”
  • Periods of unusual increased energy, nervousness, or instability
  • Sudden mood swings, increased irritability, or angry outbursts
  • Unexplained change in personality or attitude


  1. Substance Abuse and Mental Health Services Administration. Mental Health and Substance Use Disorders. 
  2.  Indian Health Service (IHS). Alcohol and Substance Abuse Program (ASAP) Information for Family and Friends: Warning Signs of Substance and Alcohol Use Disorder.