Mental Disorders
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
What are mental disorders?
Mental disorders (or mental illnesses) are conditions that affect your thinking, feeling, mood, and behavior. They may happen over a short period of time or come and go. Some can be chronic (long-lasting). They can affect your ability to relate to others and function each day..
What are some types of mental disorders?
There are many different types of mental disorders. Some common ones include:
- Anxiety disorders, including panic disorder, obsessive-compulsive disorder, and phobias
- Depression, bipolar disorder, and other mood disorders
- Eating disorders
- Personality disorders
- Post-traumatic stress disorder (PTSD)
- Psychotic disorders, including schizophrenia
What causes mental disorders?
There is no single cause for mental illness. A number of factors can contribute to risk for mental illness, such as:
- Your genes and family history
- Your life experiences, such as stress or a history of abuse, especially if they happen in childhood
- Biological factors such as chemical imbalances in the brain
- A traumatic brain injury (TBI)
- Prenatal (before birth) exposure to viruses, toxic chemicals, or other substances such as alcohol and drugs.
- Use of alcohol or recreational drugs
- Having a serious medical condition like cancer
- Having few friends, and feeling lonely or isolated
Mental disorders are not caused by character flaws. They have nothing to do with being lazy or weak.
Who is at risk for mental disorders?
Mental disorders are common. Many Americans will be diagnosed with a mental disorder at some time in their life.
How are mental disorders diagnosed?
The steps to getting a diagnosis include:
- A medical history
- A physical exam and possibly lab tests, if your provider thinks that other medical conditions could be causing your symptoms
- A psychological evaluation. You will answer questions about your thinking, feelings, and behaviors.
What are the treatments for mental disorders?
Treatment depends on which mental disorder you have and how serious it is. You and your provider will work on a treatment plan just for you. It usually involves some type of therapy. You may also take medicines. Some people also need social support and education on managing their condition.
In some cases, you may need more intensive treatment. You may need to go to a psychiatric hospital. This could be because your mental illness is severe. Or it could be because you are at risk of hurting yourself or someone else. In the hospital, you will get counseling, group discussions, and activities with mental health professionals and other patients.
Symptoms, tests and care options
Further reading selected by MedlinePlus. Links open the original organizations’ websites.
- Brain Stimulation Therapies · National Institute of Mental Health
- How to Choose a Psychologist · American Psychological Association
- Meditation and Mindfulness: Effectiveness and Safety · National Center for Complementary and Integrative Health
- Mental Health Screening · National Library of Medicine
- Mental Health: What's Normal, What's Not · Mayo Foundation for Medical Education and Research
Questions for your care team
General prompts to help prepare for your appointment.
- How does this information apply to my situation?
- Which symptoms or results need evaluation?
- Which tests are useful, and what can they tell us?
- What care options, benefits, and risks should we discuss?
- When should I seek urgent help, and whom should I call?
- When is follow-up, and how will we know whether the plan is working?
For a life-threatening emergency, call 911 in the U.S. or your local emergency number.
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