It may be difficult to identify the warning signs of substance use. You may not be able to pinpoint behaviors that symbolize hidden substance use even if they are in front of you. It is important to recognize the signs of substance use sooner rather than later so intervention can occur before addiction takes place. This is not an exhaustive list, as substance use signs vary from person to person, and from substance to substance, but the most common substance use signs include: 

Behavior and Emotional Signs of Substance Use

• Lack of control, or inability to stay away from a substance or behavior
• Decreased socialization, like abandoning commitments or ignoring relationships
• Sudden changes in friendships
• Withdrawal from usual hobbies or activities they once enjoyed
• Declining performance at work or school
• Sudden financial problems or a constant need for money
• Secretive behavior or increased desire for privacy
• Mood swings
• Aggression
• Appearing anxious, fearful, or paranoid for no reason
• Lack of motivation

Physical Signs of Short-Term Substance Use

• Sudden change in weight or appetite 
• Unusual body odor or deterioration of personal hygiene 
• Tracks of needle marks or bruises on the arm, legs, feet, or neck
• Red and watery eyes 
• Slowed or unsteady coordination
• Tremors or shaking hands, feet, or head
• Flushed face
• Tooth decay
• Pupils that are larger or smaller than normal 
• Complaints of muscle aches or pains
• Sores or open wounds
• Appearing tired or run down
• Sudden change in sleep patterns
• Runny nose or sniffling 

Long-Term Signs of Substance Use

• Cardiac complications 
• Stroke
• STDs (sexually transmitted diseases) 
• Depression
• Anxiety
• Chronic headaches and migraines 
• Memory issues 
• Gastrointestinal complications

For more information on substance use visit

• National Institute on Drug Abuse (NIDA)
• Substance Abuse and Mental Health Services Administration (SAMHSA)
• National Alliance on Mental Illness