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Overview of Anxiety Disorders


John W. Barnhill

, MD, New York-Presbyterian Hospital

Reviewed/Revised Aug 2023
Topic Resources

Anxiety is a feeling of nervousness, worry, or unease that is a normal human experience. It is also present in a wide range of mental health conditions, including generalized anxiety disorder, panic disorder, and phobias. Although each of these disorders is different, they all feature distress and dysfunction specifically related to anxiety and fear.

  • When people experience anxiety, they also often have physical symptoms, including shortness of breath, dizziness, sweating, rapid heartbeat, and/or tremor.

  • Anxiety disorders often substantially change people's daily behavior, including leading them to avoid certain things and situations.

  • These disorders are diagnosed using standard medical criteria.

  • Medications, psychotherapy, or both can substantially help most people with anxiety disorders.

Anxiety is a normal response to a threat or to psychologic stress. Normal anxiety has its root in fear and serves an important survival function. When someone is faced with a dangerous situation, anxiety triggers the fight-or-flight response. With this response, a variety of physical changes, such as increased blood flow to the heart and muscles, provide the body with the necessary energy and strength to deal with life-threatening situations, such as running from an aggressive animal or fighting off an attacker. Anxiety can help a person adapt to more ordinary stressors by motivating them to prepare, practice, and rehearse. It can even prompt a person to approach potentially dangerous situations with an appropriate amount of caution.

However, anxiety is considered a disorder when it

  • Occurs at inappropriate times

  • Occurs frequently

  • Is so intense and long-lasting that it interferes with a person's normal activities (that is to say, it leads to maladaptive behavior)

Anxiety disorders are more common than any other category of mental health disorder and affect about one third of adults in the United States at some point during their lifetime. Significant anxiety can persist for years and begin to feel normal to the person with the anxiety. For this and other reasons, anxiety disorders are often not diagnosed or treated. They can also be associated with suicidal thoughts and suicide attempts Suicidal Behavior Suicide is death caused by an act of self-harm that is intended to be lethal. Suicidal behavior includes completed suicide, attempted suicide, and suicidal ideation (thoughts and ideas). Suicide... read more .

There are many anxiety disorders:

Most of these disorders develop in adulthood, but separation anxiety and selective mutism usually start during childhood. Doctors also evaluate people who present with severe anxiety for substance-induced/medication-induced anxiety disorder and anxiety due to another medical condition.

Anxiety disorders tend to occur with other medical and mental health conditions:

How Anxiety Affects Performance

The effects of anxiety on performance can be shown on a curve. As the level of anxiety increases, performance efficiency increases proportionately, but only up to a point. As anxiety increases further, performance efficiency decreases. Before the peak of the curve, anxiety is considered adaptive because it helps people prepare for a crisis and improve their functioning. Beyond the peak of the curve, anxiety is considered maladaptive because it produces distress and impairs functioning.

How Anxiety Affects Performance

Causes of Anxiety Disorders

The causes of anxiety disorders are not fully known, but the following may be involved:

  • Environment (such as experiencing a traumatic event or stress)

  • Genetic factors (including a family history of an anxiety disorder)

  • A physical condition (for example, an overactive thyroid gland, heart failure)

  • Medications, illicit drugs, or other substances (for example, caffeine, corticosteroids, cocaine)

An anxiety disorder can be triggered by environmental stresses, such as the breakup of a significant relationship or exposure to a life-threatening disaster. However, many people develop an anxiety disorder in the absence of an identifiable trigger.

When a person responds strongly to stressors or a person is overwhelmed by events, an anxiety disorder can arise. For example, some people find speaking before a group exhilarating. But others dread it, becoming anxious with symptoms such as sweating, fear, a rapid heart rate, and tremor. Such people may avoid speaking even in a small group.

Anxiety tends to run in families. Doctors think some of this tendency may be inherited, but some is probably learned by living with anxious people.

Did You Know...

  • Anxiety disorders are the most common type of mental health disorder.

  • People with an anxiety disorder are more likely than other people to have depression.

Anxiety caused by a medical condition or medication

Anxiety can be caused by a medical disorder or the use or discontinuation (withdrawal) of a medication. Medical disorders that can cause anxiety include the following:

It is normal for people to have some level of anxiety when they have a medical condition that they fear will make them ill or even cause death. There is no right answer about how much anxiety is reasonable or excessive for any individual person or disease. However, if it causes distress or interferes with daily functioning, the person may have an anxiety disorder that needs treatment.

Even fever can cause anxiety.

Drugs, medications, or other substances that can trigger anxiety include the following:

Many people developed anxiety and trauma- and stressor-related disorders during the COVID-19 pandemic, and some people continue to have anxiety associated with the pandemic or a COVID-19 infection. Factors that caused fear and anxiety or made it worse include risk of illness or death, symptoms such as shortness of breath, treatment with corticosteroids, illness or death of a loved one, the need for preventive measures (masks, hand washing, lockdowns), and many other personal or social factors (such as major changes in daily routines, social isolation, or changes in school, work, family, or community). In addition, some experts think that COVID-19 infection induces a host immune response that leads to neuropsychiatric symptoms (for example, anxiety, mood changes, neuromuscular dysfunction). These neuropsychiatric reactions may be acute or part of a syndrome known as long COVID.

Symptoms of Anxiety Disorders

Anxiety can arise suddenly, as in panic, or gradually over minutes, hours, or days. Anxiety can last for any length of time, from a few seconds to years. It ranges in intensity from barely noticeable qualms to a full-blown panic attack Panic Attacks and Panic Disorder A panic attack is a brief period of extreme distress, anxiety, or fear that begins suddenly and is accompanied by physical and/or emotional symptoms. Panic disorder involves recurrent panic... read more , which may cause shortness of breath, dizziness, an increased heart rate, and trembling (tremor).

Anxiety disorders can induce many physical symptoms, including

  • Nausea, vomiting, diarrhea

  • Shortness of breath, choking

  • Dizziness, faintness, sweats, hot and cold flashes

  • Palpitations, accelerated heart rate

  • Muscle tension, chest pain or tightness

It can be useful for the person to keep a detailed panic or worry diary to write down descriptions of symptoms and what factors were associated with them (day, time, any known causes of the anxiety). Remembering the details to report to the doctor after the fact can be difficult. The most successful treatment strategies often depend on addressing the specific details.

Diagnosis of Anxiety Disorders

  • A doctor's evaluation, based on standard psychiatric diagnostic criteria

Deciding when anxiety is severe enough to be considered a disorder can be complicated. People's ability to tolerate anxiety varies, and determining what constitutes abnormal anxiety can be difficult. Doctors usually use the following specific established criteria:

  • Anxiety is very distressing.

  • Anxiety interferes with functioning.

  • Anxiety is long-lasting or keeps coming back.

Doctors also do a physical examination. Blood and other tests may be done to check for other medical disorders that can cause anxiety.

Treatment of Anxiety Disorders

  • Treatment of the cause, if a medical condition is found

  • Education

  • Relaxation techniques

  • Psychotherapy

  • Medications

Accurate diagnosis is important because treatment varies depending on the anxiety disorder. Additionally, anxiety disorders must be distinguished from anxiety that occurs in many other mental health disorders, which involve different treatment approaches.

If the cause of anxiety is another medical disorder or a medication, doctors aim to correct the cause. Anxiety should subside after the physical disorder is treated or the medication has been stopped long enough for any withdrawal symptoms to subside. If anxiety remains, antianxiety medications or psychotherapy (such as behavioral therapy) is used.

Many people with anxiety disorders self-medicate with substances such as alcohol, marijuana, and benzodiazepines (antianxiety medications). Not only might they be embarrassed to admit this to their doctor, but they may also be unwilling to give up these substances until their doctor comes up with a viable alternative. Self-medicating in this way is dangerous and can lead to a vicious circle of rebounding anxiety after use, followed by an urgent need to self-medicate again and again.

If an anxiety disorder is diagnosed, medications 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 (such as 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 ), alone or in combination, can significantly relieve the distress and dysfunction for most people. Different types of psychotherapies may be used, such as cognitive behavioral therapy, mindfulness-based stress reduction, hypnosis, and supportive psychotherapy.

Benzodiazepines (such as diazepam) are commonly prescribed. For many people, antidepressants, Drug 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 such as selective serotonin reuptake inhibitors (SSRIs), work as well for anxiety disorders as they do for depression.

All anxiety disorders can occur along with other mental health conditions. Doctors need to treat all conditions related to the anxiety. For example, anxiety disorders often occur along with an alcohol use disorder Alcohol Use Alcohol (ethanol) is a depressant (it slows down brain and nervous system functioning). Consuming large amounts rapidly or regularly can cause health problems, including organ damage, coma,... read more . Treating the alcohol use disorder without treating the anxiety is unlikely to be effective since the person may be using alcohol to decrease the anxiety. On the other hand, treating the anxiety without addressing the alcohol disorder may be unsuccessful because daily changes in the amount of alcohol in the blood can cause levels of anxiety to fluctuate.


More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Cafcit, NoDoz, Stay Awake, Vivarin
Diastat, Dizac, Valium, VALTOCO
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