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Treatment of Mental Illness


Michael B. First

, MD, Columbia University

Last full review/revision Mar 2020| Content last modified Mar 2020
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Extraordinary advances have been made in the treatment of mental illness. As a result, many mental health disorders can now be treated nearly as successfully as physical disorders.

Most treatment methods for mental health disorders can be categorized as either

  • Somatic

  • Psychotherapeutic

Somatic treatments include drugs, electroconvulsive therapy, and other therapies that stimulate the brain (such as transcranial magnetic stimulation and vagus nerve stimulation).

Psychotherapeutic treatments include psychotherapy (individual, group, or family and marital), behavior therapy techniques (such as relaxation training or exposure therapy), and hypnotherapy.

Most studies suggest that for major mental health disorders, a treatment approach involving both drugs and psychotherapy is more effective than either treatment method used alone.

Psychiatrists are not the only mental health care practitioners trained to treat mental illness. Others include clinical psychologists, advanced practice nurses, and social workers. However, psychiatrists (and psychiatric nurse practitioners in some states) are the only mental health care practitioners licensed to prescribe drugs. Other mental health care practitioners practice psychotherapy primarily. Many primary care doctors and other types of doctors also prescribe drugs to treat mental health disorders.


Types of Mental Health Care Practitioners





Medical doctor with 4 or more years of medical and psychiatric training after graduation from medical school

Can prescribe drugs, use electroconvulsive therapy, and admit people to the hospital

May only practice psychotherapy, only prescribe drugs, or do both


Practitioner who has a master’s or doctoral degree but not a medical degree

Often have postdoctoral training and usually have been trained to administer psychologic tests that are helpful in diagnosis

May practice psychotherapy but cannot do physical examinations, prescribe drugs (in most states), or admit people to the hospital

Psychiatric social worker

A practitioner with specialized training in certain aspects of psychotherapy, such as family and marital therapy or individual psychotherapy

Often trained to interface with the social service systems in the state

May have a master's degree and sometimes a doctorate as well

Cannot do physical examinations or prescribe drugs

Advanced practice psychiatric nurse

Registered nurse with a master’s degree or higher and training in behavioral health

May practice psychotherapy independently in some states and may prescribe drugs under the supervision of a doctor


May be a psychiatrist, psychologist, or social worker who has many years of training in the practice of psychoanalysis (a type of intensive psychotherapy involving several sessions a week and designed to explore unconscious patterns of thought, feeling, and behavior)

Practices psychoanalysis and, if also a psychiatrist, may prescribe drugs and admit people to hospitals

Drug Therapy

A number of psychoactive drugs are highly effective and widely used by psychiatrists and other medical doctors. These drugs are often categorized according to the disorder they are primarily prescribed for. For example, antidepressants are used to treat depression.

The most widely used class of antidepressants is

Other classes of antidepressants include

Tricyclic antidepressants such as amitriptyline and nortriptyline are seldom used anymore to treat depression because of their side effects. However, these drugs may be used if people also have a disorder causing chronic pain that interferes with activities and work. Tricyclic antidepressants can help relieve certain kinds of pain.

Monoamine oxidase inhibitors may be effective but are rarely used except when other antidepressants have not worked.

Older antipsychotic drugs, such as chlorpromazine, haloperidol, and thiothixene, are helpful in treating psychotic disorders such as schizophrenia and certain behavioral problems. Newer antipsychotic drugs (commonly called atypical or 2nd-generation antipsychotics) are now commonly used as initial treatment. Newer antipsychotic drugs include aripiprazole, asenapine, cariprazine, lurasidone, olanzapine, quetiapine, risperidone, and ziprasidone. For people who do not respond to other antipsychotic drugs, clozapine is being increasingly used.

SSRIs and antianxiety drugs, such as clonazepam, lorazepam, and diazepam, as well as other antidepressants, are used to treat anxiety disorders, such as panic disorder and phobias.

Mood stabilizers, such as lithium, carbamazepine, valproate, lamotrigine, and topiramate, are used to treat bipolar disorder. Also, several antipsychotic drugs can be used to treat bipolar disorder. They include aripiprazole, asenapine, cariprazine, lurasidone, olanzapine, quetiapine, risperidone, and ziprasidone.

Electroconvulsive Therapy

For electroconvulsive therapy, electrodes are placed on the head, and while the person is under anesthesia, a series of electrical shocks are delivered to the brain to induce a brief seizure. This therapy has consistently been shown to be the most effective treatment for severe depression. Many people treated with electroconvulsive therapy experience temporary memory loss. However, contrary to its portrayal in the media, electroconvulsive therapy is safe and rarely causes any other complications. The modern use of anesthetics and muscle relaxants has greatly reduced any risk.

Other brain stimulation therapies

Other therapies that stimulate the brain, such as repetitive transcranial magnetic stimulation and vagus nerve stimulation, are under study and may be beneficial for people with depression that does not respond to drugs or psychotherapy. These therapies involve activating or stimulating the brain directly with magnets or implants that stimulate the vagus nerve. The stimulated cells are thought to release chemical messengers (neurotransmitters), which help regulate mood and may thus relieve symptoms of depression.


In recent years, significant advances have been made in the field of psychotherapy, which is sometimes referred to as talk therapy. By creating an empathetic and accepting atmosphere, the therapist often is able to help the person identify the source of the problems and consider alternatives for dealing with them. The emotional awareness and insight that the person gains through psychotherapy often results in a change in attitude and behavior that allows the person to live a fuller and more satisfying life.

Psychotherapy is appropriate and effective in a wide range of conditions. Even people who do not have a mental health disorder may find psychotherapy helpful in coping with such problems as employment difficulties, bereavement, or chronic illness in the family. Group psychotherapy, couples therapy, and family therapy are also widely used.

Most mental health practitioners practice one of six types of psychotherapy:

  • Behavioral therapy

  • Cognitive therapy

  • Interpersonal therapy

  • Psychoanalysis

  • Psychodynamic psychotherapy

  • Supportive psychotherapy

Behavioral therapy

Behavioral therapy involves a number of interventions that are designed to help the person unlearn maladaptive behaviors while learning adaptive behaviors. Exposure therapy, often used to treat phobias, is one example of a behavioral therapy. In exposure therapy, people are exposed to feared objects, activities, or situations in a safe environment. The purpose is to reduce fear and help people stop avoiding the things they fear.

Behavioral therapy is related to cognitive therapy. Sometimes a combination of the two, known as cognitive-behavioral therapy, is used. The theoretical basis of behavioral therapy is learning theory, which says that abnormal behaviors are due to faulty learning.

Cognitive therapy

Cognitive therapy helps people identify distortions in thinking and understand how these distortions lead to problems in their lives. For example, people may think in an all-or-nothing way ("if I am not a total success, I am a complete failure"). The premise is that how people feel and behave is determined by how they interpret experiences. Through the identification of core beliefs and assumptions, people learn to think in different ways about their experiences, reducing symptoms and resulting in improvement in behavior and feelings.

Interpersonal therapy

Interpersonal therapy was initially conceived as a brief psychologic treatment for depression and is designed to improve the quality of a depressed person’s relationships. It focuses on the following:

  • Unresolved grief

  • Conflicts that arise when people have to fill roles that differ from their expectations (such as when a woman enters a relationship expecting to be a stay-at-home mother and finds that she must also be the major provider for the family)

  • Transitions in social roles (such as going from being an active worker to being retired)

  • Difficulty communicating with others

The therapist teaches the person to improve aspects of interpersonal relationships, such as overcoming social isolation and responding in a less habitual way to others.


Psychoanalysis is the oldest form of psychotherapy and was developed by Sigmund Freud in the first part of the 20th century. The person typically lies on a couch in the therapist’s office 4 or 5 times a week and attempts to say whatever comes to mind—a practice called free association. Much of the focus is on helping the person understand how past patterns of relationships repeat themselves in the present. The relationship between the person and the therapist is a key part of this focus. An understanding of how the past affects the present helps the person develop new and more adaptive ways of functioning in relationships and in work settings.

Psychodynamic psychotherapy

Psychodynamic psychotherapy, like psychoanalysis, emphasizes the identification of unconscious patterns in current thoughts, feelings, and behaviors. However, the person is usually sitting instead of lying on a couch and attends only 1 to 3 sessions per week. In addition, less emphasis is placed on the relationship between the person and therapist.

Supportive psychotherapy

Supportive psychotherapy, which is most commonly used, relies on the empathetic and supportive relationship between the person and the therapist. It encourages expression of feelings, and the therapist provides help with problem solving. Problem-focused psychotherapy, a form of supportive therapy, may be used successfully by primary care doctors.

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