ConditionMental health & sleep
Psychiatric Disorders: An Overview of Mental Illness
Psychiatric disorders, also called mental health disorders or mental illnesses, are health conditions that change how a person thinks, feels, behaves or relates to others, causing distress or difficulty functioning. They are common: about 1 in 5 US adults has one in a given year. The main groups include anxiety disorders, depression and bipolar disorder, psychotic disorders, trauma-related disorders, eating disorders, substance use disorders and neurodevelopmental conditions. Most are treatable with talking therapies, medicines and support.
Also called: Mental health disorders, mental illnesses, psychiatric illness, mental disorders
At a glance
- What they are
- Health conditions affecting thoughts, emotions and behavior that cause distress or impair daily life.
- How common
- About 1 in 5 US adults each year. Half of all mental illness begins by age 14.
- Main groups
- Anxiety, mood, psychotic, trauma-related, obsessive-compulsive, eating, substance use, personality and neurodevelopmental disorders.
- Diagnosis
- Clinical interview using DSM-5-TR or ICD-11 criteria, plus a physical check to rule out medical causes.
- Treatment
- Psychotherapy, medicines, lifestyle changes, peer and family support, and crisis services.
When to get help
Call 911 or go to the ER
- Thoughts of suicide, a plan or intent, or recent self-harm: call or text 988 (US), or call 911 or your local emergency number
- Risk of harming someone else
- Severe confusion, hearing voices telling you to hurt yourself or others, or being unable to care for yourself
- Overdose, or severe intoxication or withdrawal
See a doctor within a day or two
- New hallucinations, paranoia or strange beliefs
- Several days without sleep with racing thoughts, risky behavior or grandiose ideas (possible mania)
- Not eating, rapid weight loss or fainting with an eating disorder
- A rapid change in personality or confusion in an older adult (rule out medical causes such as delirium)
Book a routine appointment
- Low mood, worry, irritability or loss of interest lasting more than 2 weeks
- Difficulty functioning at work, school or home
- Using alcohol or drugs to cope
- Concerns about attention, learning or development in a child
Usually safe to manage at home
- Short periods of stress or sadness after life events that improve with rest, support and routine
What makes something a psychiatric disorder
Everyone has difficult emotions. A psychiatric disorder is diagnosed when symptoms:
- meet established criteria (from the DSM-5-TR or ICD-11)
- last a defined length of time
- cause significant distress or interfere with work, school, relationships or self-care
- are not better explained by a medical condition, medicine or substance
Main types of psychiatric disorders
| Group | Examples | Typical features |
|---|---|---|
| Anxiety disorders | Anxiety (generalized anxiety disorder), panic disorder, social anxiety, phobias | Excessive fear or worry, physical tension, avoidance |
| Depressive disorders | Depression, persistent depressive disorder | Low mood, loss of interest, sleep and appetite changes |
| Bipolar disorders | Bipolar disorder I and II | Episodes of depression and mania or hypomania |
| Psychotic disorders | Schizophrenia, schizoaffective disorder | Hallucinations, delusions, disorganized thinking |
| Trauma and stress-related | PTSD, adjustment disorder | Symptoms after a traumatic or stressful event |
| Obsessive-compulsive and related | OCD, body dysmorphic disorder, hoarding | Intrusive thoughts and repetitive behaviors |
| Eating disorders | Anorexia, bulimia, binge-eating disorder | Disturbed eating, weight and body image |
| Substance use disorders | Alcohol, opioid, stimulant, cannabis use disorders | Loss of control over use despite harm |
| Personality disorders | Borderline, antisocial personality disorder | Long-standing patterns affecting relationships |
| Neurodevelopmental | ADHD, autism spectrum disorder, intellectual disability | Begin in childhood |
| Neurocognitive | Dementia, delirium | Decline in memory and thinking |
| Sleep-wake disorders | Insomnia, narcolepsy | Disturbed sleep affecting daytime function |
Warning signs
- persistent sadness, hopelessness or emptiness
- excessive worry or fear
- extreme mood swings
- withdrawal from friends and activities
- major changes in sleep or appetite
- difficulty concentrating
- unusual thinking, hearing or seeing things others do not
- increased use of alcohol or drugs
- unexplained physical complaints
- thoughts of death or suicide
Causes and risk factors
Psychiatric disorders arise from a combination of:
- genetics: many conditions run in families
- brain biology: differences in brain circuits and chemical signaling
- life experiences: trauma, abuse, neglect and adverse childhood experiences
- stress: loss, poverty, discrimination, isolation, chronic illness
- substance use
- physical health: thyroid disease, brain injury, chronic pain and other conditions
They are not caused by weakness or a lack of willpower.
Diagnosis
A doctor, psychiatrist, psychologist or other licensed clinician will:
- talk through symptoms, their duration and impact
- ask about personal and family history, substances and safety
- use questionnaires such as the PHQ-9 for depression or GAD-7 for anxiety
- perform a physical exam and blood tests when needed to exclude medical causes
Treatment
Psychotherapy
- cognitive behavioral therapy (CBT): effective for anxiety, depression, OCD, insomnia and more
- dialectical behavior therapy (DBT) for emotional dysregulation and self-harm
- trauma-focused therapies such as prolonged exposure, cognitive processing therapy and EMDR
- family-based treatment for eating disorders in young people
- interpersonal and psychodynamic therapies
Medicines
- antidepressants (SSRIs, SNRIs and others) for depression and anxiety
- mood stabilizers (lithium, certain anticonvulsants) for bipolar disorder
- antipsychotics for psychotic disorders and some mood disorders
- stimulants and non-stimulants for ADHD
- medicines for addiction: buprenorphine, methadone and naltrexone for opioid use disorder. Naltrexone and acamprosate for alcohol use disorder
Other treatments
- electroconvulsive therapy (ECT) and transcranial magnetic stimulation (TMS) for severe or treatment-resistant depression
- peer support, supported employment and housing
- crisis services and hospital care when needed
Self-care that supports recovery
- regular sleep and physical activity
- limiting alcohol and avoiding drugs
- staying connected with others
- learning stress-management skills
Getting help
- talk to your primary care doctor, who can assess and refer
- in the US, call or text 988 for the Suicide and Crisis Lifeline, available 24/7
- SAMHSA's National Helpline (1-800-662-4357) offers free, confidential treatment referrals
Frequently asked questions
What are the most common psychiatric disorders?
Anxiety disorders are the most common, followed by depression, substance use disorders, ADHD, PTSD and bipolar disorder. Many people have more than one condition at the same time.
What causes psychiatric disorders?
They result from a mix of genetic, biological, psychological and social factors, including family history, brain chemistry, trauma, chronic stress, substance use and physical illness. They are not caused by personal weakness.
Can psychiatric disorders be cured?
Many conditions can go into full remission with treatment, such as depression and anxiety disorders. Others, such as bipolar disorder and schizophrenia, are long term but can be managed so people live full, productive lives.
How do I know if I need help for my mental health?
Seek help if symptoms last more than 2 weeks, cause significant distress, or interfere with work, school, relationships or self-care. Get help immediately for thoughts of suicide or self-harm by calling or texting 988 in the US.
What is the difference between a psychiatrist and a psychologist?
A psychiatrist is a medical doctor who can diagnose mental illness, prescribe medicine and provide therapy. A psychologist has a doctoral degree in psychology and provides assessment and psychotherapy but, in most US states, does not prescribe.
Sources
This guide was written from current patient and clinical guidance, including:
- American Psychiatric Association: DSM-5-TR and What is mental illness?
- National Institute of Mental Health (NIMH): Mental illness statistics; Health topics
- World Health Organization: Mental disorders fact sheet
- SAMHSA: National Survey on Drug Use and Health
- 988 Suicide and Crisis Lifeline