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Suicidal Behavior


Christine Moutier

, MD, American Foundation For Suicide Prevention

Reviewed/Revised Jul 2021 | Modified Sep 2022
Topic Resources

Suicide is death caused by an intentional act of self-harm that is designed to be lethal. Suicidal behavior includes completed suicide, attempted suicide, and suicidal ideation.

The terminology used to describe suicide has evolved over time to reflect advances in the scientific study of suicidal behavior, growing advocacy for the victims and survivors of suicide, and reduction of the stigma associated with suicide.

Suicidal behavior includes the following:

  • Completed suicide: An intentional act of self-harm that results in death.

  • Attempted suicide: An act of self-harm that is intended to result in death but does not. A suicide attempt may or may not result in injury.

  • Suicidal ideation: Thoughts, plans, and preparatory acts about suicide.

Nonsuicidal self-injury Nonsuicidal Self-Injury Nonsuicidal self-injury is a self-inflicted act that causes pain or superficial damage but is not intended to cause death. Although the methods people use to hurt themselves, such as cutting... read more (NSSI) is an act of self-harm that is not intended to result in death. Such acts include inflicting scratches or cuts on the arms, burning oneself with a cigarette, and overdosing on vitamins. Nonsuicidal self-injury may be a way to reduce tension because physical pain may relieve psychologic pain. It may also be a plea for help from people who still wish to live. These acts should not be dismissed lightly because people with a history of NSSI have a higher risk of suicide over the long term.

Information about the frequency of suicide comes mainly from death certificates and inquest reports and probably underestimates the true rate. Even so, suicidal behavior is an all-too-common health problem. Suicidal behavior occurs in men and women of all ages, races, creeds, incomes, educational levels, and sexual orientations. There is no typical suicide profile, although some groups of people, such as middle-aged and older males, American Indian youth, and LGBTQ people (not a complete list), have a higher risk of suicide than others.

Completed suicide worldwide

Worldwide, almost 800,000 people die by suicide every year.

In the United States, suicide was the second leading cause of death among people aged 10 to 34 years.

Evidence suggests that for each person who dies by suicide, there are many more people who attempt suicide. This ratio varies widely by country, region, sex, age, and method.

Completed suicide in the United States

In the United States, there were almost 48,000 completed suicides in 2019. On average, there are about 132 suicides each day.

In 2019, the suicide rate was highest in people aged 45 to 64. No one knows for certain why this is, but the following factors may have played a role:

The second highest rate of suicide occurs in people aged 75 years and older, likely because of loneliness, isolation, and infirmity.

Suicide generally ranks 10th overall as a cause of death in the United States but declined to 11th in 2020 because of the large number of deaths caused by the COVID-19 pandemic.

In all age groups, men who die by suicide outnumber women almost 4 to 1. The reasons are unclear, but the following may be involved:

In 2019, the suicide rate was highest among non-Hispanic Whites, followed by American Indians and Alaskan natives. For the most current statistics on suicide, see the data collected by the American Foundation for Suicide Prevention.

Did You Know?

  • Suicide is a leading cause of death among young people, but the rate of completed suicides is highest in people aged 45 to 64 and second highest in people aged 75 and over.

  • Men are 4 times more likely to take their lives than women.

  • For every person who dies by suicide, there are many more who attempt it.

Attempted suicide in the United States

In 2019, an estimated 1.4 million American adults attempted suicide. There are an estimated 25 attempts for every completed suicide. Many people make repeated attempts. However, only 5 to 10% of people who make an attempt eventually die by suicide. Suicide attempts are particularly common among adolescent girls. Girls aged 15 to 19 make 100 suicide attempts for every suicide completed. Across all age groups, women attempt suicide 2 or 3 times as often as men, but men are 4 times more likely to die in their attempts. Older people attempt suicide 4 times for every completed suicide.


About one in six people who kill themselves leaves a suicide note, which sometimes provides clues as to why. Reasons given include mental illness, feelings of hopelessness, feeling like a burden to others, and inability to cope with various life stresses.

Research has shown that many people who completed suicide were experiencing multiple risk factors at the time of death. About 85 to 95% of people who die by suicide have a diagnosable mental health condition at the time of their death.

The most common factor that contributes to suicidal behavior is

Depression, including the depression that is part of bipolar disorder, Bipolar Disorder In bipolar disorder (formerly called manic-depressive illness), episodes of depression alternate with episodes of mania or a less severe form of mania called hypomania. Mania is characterized... read more is involved in over 50% of attempted suicides and an even higher percentage of completed suicides. Depression can occur out of the blue, be triggered by a recent loss or other distressing event, or result from a combination of factors. In people with depression, marital problems, recent arrest or trouble with the law, unhappy or ended love affairs, disputes with parents or bullying (among adolescents), or the recent loss of a loved one (particularly among older people) may trigger a suicide attempt. The risk of suicide is higher if people with depression also have significant anxiety. Overview of Anxiety Disorders Anxiety is a feeling of nervousness, worry, or unease that is a normal human experience. It is also present in a wide range of psychiatric disorders, including generalized anxiety disorder,... read more

Traumatic childhood experiences, particularly including physical and sexual abuse, increase the risk of attempted suicide.

Use of alcohol may intensify depression, which, in turn, makes suicidal behavior more likely. Alcohol also reduces self-control and increases impulsivity. About 30% of people who attempt suicide drink alcohol before the attempt, and about half of them are intoxicated at the time. Because alcohol use, particularly binge drinking, often causes deep feelings of remorse during dry periods, people who engage in unhealthy alcohol use are at higher risk of suicide.

Almost all other mental health conditions also put people at higher risk of suicide.

People with schizophrenia Schizophrenia Schizophrenia is a mental disorder characterized by loss of contact with reality (psychosis), hallucinations (usually, hearing voices), firmly held false beliefs (delusions), abnormal thinking... read more or other psychotic disorders may have delusions (fixed false beliefs) that they find impossible to cope with, or they may hear voices (auditory hallucinations) commanding them to kill themselves. Also, people with schizophrenia are prone to depression. As a result, they die by suicide at a much higher rate (10%) than the general population.

Isolation increases the risk of suicidal behavior. People who have been separated, divorced, or widowed are more likely to complete suicide. Suicide is less common among people who are in a secure relationship than among single people.

Risk Factors for Suicidal Behavior

  • Aggressive or impulsive behavior

  • Being an American Indian, an Alaskan native, or male

  • Bereavement or loss

  • Bullying (for example, cyberbullying, social rejection, discrimination, humiliation, disgrace)

  • Depression (especially when accompanied by anxiety, as part of bipolar disorder, or associated with recent hospitalization) and other mental disorders

  • Drug or alcohol use disorders

  • Feelings of sadness or hopelessness (when persistent)

  • Financial stress from economic downturns, debt, or underemployment

  • Living alone

  • Medical illness, particularly one that is painful or disabling, or affects the brain

  • Relationship conflict

  • Suicide, including current preoccupation with, well-defined plans for, family history of, and/or previous attempts at

  • Traumatic childhood experiences, including physical or sexual abuse

  • Work disruption (for example, unemployment) and periods of transition (for example, going from active duty to veteran status, retiring)

Antidepressants and the risk of suicide

The risk of suicide attempts is greatest in the month before starting antidepressant treatment, and the risk of death by suicide is no higher after antidepressants are started. However, antidepressants sometimes slightly increase the frequency of suicidal thoughts and attempts (but not of completed suicide) in children, adolescents, and young people. So parents of children and adolescents should be warned about this risk, and children and adolescents should be carefully monitored for the following side effects, especially during the first few weeks after they start taking the drug:

  • Increased anxiety

  • Agitation

  • Restlessness

  • Irritability

  • Anger

A shift into hypomania Hypomania In bipolar disorder (formerly called manic-depressive illness), episodes of depression alternate with episodes of mania or a less severe form of mania called hypomania. Mania is characterized... read more (when people feel full of energy and cheerful but are often easily irritated, distracted, and agitated) is also an important side effect to watch out for.

Clinicians, patients, and families should bear in mind that suicidality is a core feature of depression. Treatments that alleviate depression reduce the risk of suicide.

Because of public health warnings about the possible association between taking antidepressants and an increased risk of suicide, doctors began diagnosing depression less and started prescribing antidepressants more than 30% less often for children and young people. However, during this same time, suicide rates among young people temporarily increased by 14%. Thus, it is possible that by discouraging drug treatment of depression, these warnings resulted in more, not fewer, deaths by suicide.

When people with depression are given antidepressants, doctors take certain precautions to reduce the risk of suicidal behavior:

  • Giving people antidepressants in amounts that would not cause death

  • Scheduling more frequent visits when treatment is first started

  • Clearly warning people and their family members and significant others to be alert for worsening symptoms, agitation, insomnia, or suicidal ideation

  • Instructing people and their family members and significant others to immediately call the doctor who prescribed the antidepressant or to seek care elsewhere if symptoms worsen or suicidal thoughts occur

Did You Know?

  • Taking antidepressants has been linked with an increased risk of suicidal thoughts and attempts in youth under age 24, but not addressing depression with appropriate treatment (which can include drugs and/or therapy) may increase the risk of suicide much more.

  • Making the home environment safe is one important way to effectively reduce the risk of suicide. Removing lethal means by securing firearms, drugs, and toxic substances can be life-saving.

Suicide contagion

Suicide contagion refers to a phenomenon in which one suicide seems to lead to others in a community, school, or workplace. Highly publicized suicides may have a very wide effect. Adolescents and young adults are especially vulnerable to contagion effects. They may be exposed directly because they know someone who attempts or dies by suicide. They may also be indirectly exposed by round-the-clock, sensationalized, graphic media coverage of a celebrity's death. Conversely, media coverage with positive messaging about a suicide death can decrease the risk of suicide contagion for vulnerable youth. Positive messaging typically communicates clearly about the tragic loss of a community member and goes on to express support for the grieving community. Messaging should describe mental health struggles as part of life and point out there is no stigma related to seeking help and treatment. Such portrayal of mental health and suicide can have a positive public health impact, rather than endangering vulnerable viewers.

Suicide contagion may be a factor in an estimated 1 to 5% of all adolescent suicides. School administrators, mental health professionals, and other community leaders can learn to use the media and social platforms to stop the spread of suicide contagion. Sensitive reporting and the enforcement of postvention (an intervention conducted after a suicide) guidelines in schools and workplaces are two strategies for preventing additional suicides.

Other categories of suicide

There are several other categories of suicide that are extremely rare:

  • Group suicides

  • Murder/suicides

  • "Suicide by cop" (the result of the victim deliberately provoking law enforcement officers to use deadly force)


The choice of method is often influenced by cultural factors and availability of lethal means (for example, firearms). It may or may not reflect the seriousness of intent. Some methods (such as jumping from a tall building) make survival less likely, whereas other methods (such as overdosing on drugs) make rescue more possible. However, even if a person uses a method that proves not to be fatal, the intent may have been just as serious as that of a person whose method was fatal.

Suicide attempts most often involve drug overdose and self-poisoning. Violent methods, such as shooting and hanging, are uncommon among suicide attempts because they usually result in death.

About 50% of completed suicides in the United States involve guns. Men use this method more than women. Other methods include hanging, poisoning, jumping from a height, and cutting.

Worldwide, poisoning with pesticides accounts for a significant portion of suicides, particularly in Asia, where dangerous pesticides are widely available.


Although some attempted or completed suicides come as a shock to family members and friends, many people give warnings. Signs of distress or suicidal thoughts to look for include any change in the person's usual behavior pattern, such as changes in mood, behavior, sleep, or energy. Because most suicidal people often do not speak directly about their thoughts and distress, it is important to note when things people say suggest they may be feeling hopeless, overwhelmed, trapped, or that they are a burden to others. Changes in behavior include withdrawal from usual activities, agitation, anger outbursts, irritability, drinking or using drugs more than usual, or other odd behaviors such as saying goodbyes or giving away possessions. Any mention of suicidal thoughts even in the form of a joke and certainly any suicide attempt must be taken seriously. If it is ignored, a life may be lost.

If a person is imminently in the process of attempting suicide or has already attempted suicide, the authorities should be contacted immediately (in the United States by calling 911) so that emergency services can arrive as soon as possible. Until help arrives, stay with the person and speak in a calm, nonjudgmental, supportive manner.

A doctor may hospitalize people who have threatened or attempted suicide. Most states allow doctors to hospitalize people against their wishes if the doctors believe that those people are at high risk of harming themselves or others.

Newer comprehensive public health policies for preventing suicides use multiple methods, including suicide prevention training and trained peer counselors in schools and workplaces. Improvement in access to mental health care includes providing suicide risk–reducing clinical interventions in mental health care settings as well as in primary care offices and emergency departments. Recently, the development of artificial intelligence on social media platforms has helped to identify at-risk individuals and provide timely assistance. Public health policies that make lethal means less accessible are also prevention measures.

Suicide Intervention: National Suicide Prevention Lifeline

People imminently planning suicide are in crisis. The National Suicide Prevention Lifeline (1-800-273-TALK) provides crisis intervention for such people throughout the United States. Suicide prevention centers are staffed by specially trained personnel and volunteers.

When potentially suicidal people call the hotline, a trained counselor may do any or all of the following:

  • Seek to establish a supportive rapport

  • Facilitate a conversation that allows the person to feel heard and to move from a highly charged emotional state to a calm state where flexible coping strategies can be resumed

  • Offer constructive help for the problem that brought on the crisis and encourage them to take positive action to resolve it

  • Provide mental health resources for follow-up

  • Facilitate emergency face-to-face professional help for them only if needed


Health care professionals take any suicidal act seriously, but the plan for safety and treatment is customized to the person's situation.

If people seriously injure themselves, doctors evaluate and treat the injury and typically admit the person to the hospital. If people have taken an overdose of a potentially lethal drug, doctors immediately take steps to prevent absorption of the drug and speed its elimination from the body. People are also given any available antidote and provided with supportive care, such as a breathing tube.

After the initial evaluation, people who have attempted suicide are referred to a psychiatrist, who tries to identify problems that contributed to the attempt and plan appropriate treatment.

To identify problems, psychiatrists do the following:

  • Listen to the person's story and history leading up to the attempt or crisis

  • Try to understand what some of the underlying risk factors for suicide are, what specific events led up to the attempt, and where and how it occurred

  • Ask about symptoms of mental health conditions that may increase the risk of suicidal behavior

  • Ask whether the person is being treated for a mental illness, including whether the person is taking any drugs to treat it, has been in therapy or any other treatment modalities

  • Evaluate the person's mental state, looking for signs of depression, anxiety, agitation, panic attacks, psychosis, severe insomnia, other mental illnesses, and alcohol or substance use

  • Take a thorough medical and family history

  • Ask about personal and family relationships as well as social networks, because they are often relevant to the suicide attempt and the follow-up treatment

  • Talk to close family members and friends, and ask them about the person's use of alcohol, marijuana, pain medications or illicit opioids, and other recreational drugs

  • Help the person identify situations, events, places, thoughts, or emotional states that trigger thoughts of suicide and help the person plan ways to deal with the triggers

Because depression increases the risk of suicidal behavior, doctors carefully monitor people with depression for suicidal behavior and thoughts. For people with depression, Depression A short discussion of prolonged grief disorder. Depression is a feeling of sadness and/or a decreased interest or pleasure in activities that becomes a disorder when it is intense enough to... read more suicide risk can increase during periods when depression is more severe, as well as when several other risk factors are also present. Doctors may be able to treat depression effectively with drugs and/or psychotherapy, Psychotherapy 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... read more and thereby reduce suicide risk overall.

Some evidence suggests that using lithium, antidepressants, and newer antipsychotics to treat mood disorders in people who are at risk of suicide may reduce the number of completed suicides. Treating schizophrenia with clozapine reduces the risk of suicide.

The risk of suicide changes over time, with the most serious acute risk lasting from hours to days. Yet, according to a 2018 report of suicide risk, in a majority of suicides, people had been assessed in a variety of health care settings before their suicide, but their suicide risk was not detected. These findings highlight the importance of adopting public health strategies to reduce the risk of suicide in these people. For example, doctors should do the following:

  • Routinely screen patients for suicidal thoughts, depression, and other symptoms of distress

  • Use a caring, supportive, nonjudgmental response

  • Provide interventions to ensure the person's safety, such as using a Safety Plan and counseling on lethal means

  • Communicate with the family

Because of the increased risk of suicide following a person's discharge from an emergency department (ED) or psychiatric facility, current advocacy efforts in some countries are aimed at reforming the crisis-response system to create a wider, more robust safety net that does not rely on return visits to the ED or the intervention of law enforcement officers. Some helpful steps doctors can take to assist in this new crisis-response model, either during hospitalization and/or at discharge, include

  • Providing the person with access to crisis resources

  • Counseling the person on how to remove or safely store any potentially lethal means or substances

  • Referring the person to a qualified psychiatrist, psychotherapist or other mental health professional

  • Scheduling more frequent outpatient visits and communicating more closely with the person between visits

There are strategies that health systems can employ to reduce suicide among the highest-risk patients. One such framework is called Zero Suicide, which advocates for universal training in suicide screening for all health system staff, the use of the electronic health record to help facilitate better patient care, and the use of the above brief interventions (safety planning, lethal means counseling, strong communication with the patient and family when possible, and appropriate referrals and follow-up).

Newer evidence-based interventions can reduce suicide risk in high-risk individuals. These include cognitive behavioral therapy Behavioral therapy 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... read more (CBT), dialectical behavior therapy Treatment (DBT), and some forms of family therapy such as attachment-based family therapy. People who are identified to be at risk for suicide should be encouraged to pursue one of these types of therapy and to consider taking drugs individualized to their needs. As with any health condition, adjusting treatment when needed and providing follow-up care are important ways to optimize treatment.


Death by suicide has a marked emotional effect on all involved. Family, friends, and doctors may feel guilt, shame, and remorse at not having prevented the suicide. They may also feel anger toward the person. Eventually, they may work through these complicated grief experiences and cope with the loss.

Sometimes a grief counselor or a support group can help family and friends deal with their feelings of guilt and sorrow. The primary care doctor or local mental health service (for example, at the county or state level) can often help locate these resources. In addition, national organizations, such as the American Foundation for Suicide Prevention, maintain directories of local suicide loss survivor support groups. Resources are also available on the internet.

The effect of attempted suicide is similar. However, family members and friends have the opportunity to resolve their feelings by learning more about suicide, mental health treatment, and ways to be supportive and responsive to the individual.

Physician Aid in Dying (formerly, Assisted Suicide)

Physician aid in dying refers to the assistance given by physicians to people who wish to end their lives. It is very controversial because it reverses the doctor's usual goal, which is to preserve life. However, physician aid in dying is legal in 10 U.S. states (California, Colorado, Hawaii, Maine, Montana, New Jersey, New Mexico, Oregon, Vermont, and Washington) and the District of Columbia. It is also now under consideration in more than 15 other states. In the rest of the United States, doctors can provide treatment to minimize physical and emotional suffering, but they cannot intentionally hasten death.

Physician-assisted suicide is also legal in Switzerland, Belgium, Germany, and Canada, as well as in some other countries.

More Information

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  • American Foundation for Suicide Prevention: Provides those who struggle or who have struggled with suicide—including those who have lost loved ones to it—with access to support groups and a crisis helpline; information on implementing screening programs, establishing prevention programs in schools, and advocating for suicide prevention; and facts about suicide from prevalence statistics to public policy priorities.

  • CDC: Suicide Prevention: Provides access to fact sheets, information on risk and protective factors, prevention strategies, and other suicide-prevention organizations. Resources also available in Spanish.

  • Crisis Text Line: Provides 24/7 support via text for anyone in distress in the United States, Canada, the United Kingdom, and Ireland.

  • National Suicide Prevention Lifeline: Provides 24/7 support for people in distress. Provides information formatted for the deaf and hard of hearing. Content also available in Spanish.

  • Now Matters Now: A research-based web site that provides self-care strategies to people who experience suicidal thoughts.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Eskalith, Eskalith CR, Lithobid
Clozaril, Fazaclo, VERSACLOZ
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