Symptoms and Signs of Mental Illness in Children and Teens

Also known as clinical depression or major depressive disorder, major depression is marked by pervasive symptoms, lasting for at least two weeks and significantly affecting daily functioning. Some teens experience other forms of depression, such as seasonal depression and chronic depression.

Generalized anxiety disorder manifests as constant worrying, irrational fears, and self-judgment, which can be paralyzing for teens. Also common in teens, social anxiety is a type of anxiety disorder that catalyzes intense fear and distress in connection with social situations, meeting new people, or being the center of attention. Phobias are another form of anxiety disorder.

PTSD is a response to acute or chronic trauma in which teens experience symptoms that interfere with daily functioning, such as flashbacks, panic attacks, hyperarousal, and difficulty focusing.

A behavioral addiction, or process addiction, is a compulsion to continually engage in an activity or behavior (such as gaming, gambling, or shopping) even though it creates significant negative consequences.

Self-harm refers to injuring or hurting yourself on purpose. Officially known as non-suicidal self-injury (NSSI), self-harm is a symptom of extreme emotional distress. Hence, self-harm is one of the signs of mental illness in children and teenagers

• Relational trauma—a disrupted relationship with parents or caregivers early in life
• Other forms of adverse childhood experiences (ACEs), such as abuse, neglect, the death of a parent, or having a parent with a mental health or substance use disorder
• Living in an unsafe environment or neighborhood
• Bullying or rejection by peers
• Sexual assault
• Discrimination or exclusion due to gender identity, sexual orientation, or ethnicity
• Having a physical or intellectual disability or a chronic illness.

When any of these conditions are present, the possibility of experiencing one of the common mental disorders in teens increases exponentially.

• Sleeping too much or not enough, always tired
• Anger, aggression, withdrawal, or other behavior changes
• Changes in appetite, dramatic weight loss or gain
• Crying all the time
• Sudden drop in academic performance
• Behavioral addictions, such as gaming disorder or social media addiction
• Risky behavior, including substance abuse as an unhealthy coping mechanism for emotional distress

Parents can also watch for indications of the internal symptoms typical of common mental health disorders in teens:

• Feelings of numbness and emptiness
• Suicidal thoughts and plans
• Sense of worthlessness and guilt
• Extremely low self-esteem
• Persistent sadness and hopelessness
• Difficulty getting motivated or completing tasks
• Unexplained physical symptoms, such as aches and pains, headaches, and stomach problems
• Self-harming behaviors

In addition to the signs of mental illness in children and teens listed above, parents should also watch for symptoms of a potential mental health crisis that requires immediate medical attention. When a teen is having difficulty thinking, concentrating, or speaking coherently, it’s important to get help as quickly as possible. Other warning signs include auditory or visual hallucinations, such as ringing sounds or seeing lights. Teens in crisis may have delusions, including feeling indestructible or beyond human. Or they may experience dissociation—a sense of detachment from reality.

All of these signs of mental illness in teenagers should be taken extremely seriously. In addition, self-harm, suicidality, or a suicide attempt all indicate an immediate need for treatment. That may mean going to the emergency room or calling 911 or the National Suicide Prevention Hotline at 800-273-TALK.