In addition to anxiety, people often also 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 specific established criteria.
Drugs, psychotherapy, or both can substantially help most people.
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.
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
Anxiety disorders are more common than any other category of mental health disorder and affect about 15% of adults in the United States. 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.
Anxiety disorders include
The mental distress that occurs immediately or shortly after experiencing or witnessing an overwhelming traumatic event is no longer classified as an anxiety disorder. Such disorders are now classified as trauma and stressor-related disorders Overview of Trauma- and Stress-Related Disorders Trauma- and stress-related disorders result from exposure to a traumatic or stressful event. Specific disorders include acute stress disorder and posttraumatic stress disorder. These disorders... read more and include acute stress disorder Acute Stress Disorder Acute stress disorder is an intense, unpleasant, and dysfunctional reaction beginning shortly after an overwhelming traumatic event and lasting less than a month. If symptoms persist longer... read more , adjustment disorder Adjustment Disorder Adjustment disorders involve markedly distressing and impairing emotional and/or behavioral symptoms caused by an identifiable stressor. (See also Overview of Trauma- and Stress-Related Disorders... read more , and posttraumatic stress disorder Posttraumatic Stress Disorder (PTSD) Posttraumatic stress disorder (PTSD) involves intense, unpleasant, and dysfunctional reactions beginning after an overwhelming traumatic event. Events that threaten death or serious injury can... read more .
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.  |
Causes of Anxiety Disorders
The causes of anxiety disorders are not fully known, but the following may be involved:
Genetic factors (including a family history of an anxiety disorder)
Environment (such as experiencing a traumatic event or stress)
Psychologic makeup
A physical condition
An anxiety disorder can be triggered by environmental stresses, such as the breakup of a significant relationship or exposure to a life-threatening disaster.
When a person's response to stresses is inappropriate 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.
Anxiety caused by a physical disorder or drug
Anxiety can also be caused by a general medical disorder or the use or discontinuation (withdrawal) of a drug. General medical disorders that can cause anxiety include the following:
Heart disorders, such as heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more
and abnormal heart rhythms Overview of Abnormal Heart Rhythms Abnormal heart rhythms (arrhythmias) are sequences of heartbeats that are irregular, too fast, too slow, or conducted via an abnormal electrical pathway through the heart. Heart disorders are... read more 
(arrhythmias)Hormonal (endocrine) disorders, such as an overactive adrenal gland ( hyperadrenocorticism Cushing Syndrome In Cushing syndrome, the level of corticosteroids is excessive, usually due to taking corticosteroid drugs or overproduction by the adrenal glands. Cushing syndrome usually results from taking... read more
) or thyroid gland ( hyperthyroidism Hyperthyroidism Hyperthyroidism is overactivity of the thyroid gland that leads to high levels of thyroid hormones and speeding up of vital body functions. Graves disease is the most common cause of hyperthyroidism... read more 
) or a hormone-secreting tumor called a pheochromocytoma Pheochromocytoma A pheochromocytoma is a tumor that usually originates from the adrenal glands’ chromaffin cells, causing overproduction of catecholamines, powerful hormones that induce high blood pressure and... read more Lung (respiratory) disorders, such as asthma Asthma Asthma is a condition in which the airways narrow—usually reversibly—in response to certain stimuli. Coughing, wheezing, and shortness of breath that occur in response to specific triggers are... read more
and chronic obstructive pulmonary disease Chronic Obstructive Pulmonary Disease (COPD) Chronic obstructive pulmonary disease is persistent narrowing (blocking, or obstruction) of the airways occurring with emphysema, chronic obstructive bronchitis, or both disorders. Cigarette... read more 
(COPD)
Even fever can cause anxiety.
Anxiety may occur in dying people as a result of fear of death, pain, and difficulty breathing ( see Depression and Anxiety Depression and Anxiety Many fatal illnesses cause similar symptoms, including pain, shortness of breath, digestive problems, incontinence, skin breakdown, and fatigue. Depression and anxiety, confusion and unconsciousness... read more ).
Drugs that can trigger anxiety include the following:
Caffeine
Many prescription drugs, such as corticosteroids
Some over-the-counter weight-loss products, such as those containing the herbal product guarana, caffeine, or both
Withdrawal from alcohol Detoxification and rehabilitation Alcohol (ethanol) is a depressant. Consuming large amounts rapidly or regularly can cause health problems, including organ damage, coma, and death. Genetics and personal characteristics may... read more or sedatives Detoxification and rehabilitation Antianxiety and sedative drugs are prescription drugs used to relieve anxiety and/or help with sleep, but their use can result in dependency and a substance use disorder. Using prescription... read more , such as benzodiazepines (used to treat anxiety disorders; see the appropriate entry in the table Drugs Used to Treat Anxiety Disorders Drugs Used to Treat Anxiety Disorders 
), can cause anxiety and other symptoms, such as insomnia Insomnia and Excessive Daytime Sleepiness (EDS) The most commonly reported sleep-related problems are insomnia and excessive daytime sleepiness. Insomnia is difficulty falling asleep or staying asleep, waking up early, or a disturbance in... read more and restlessness.
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 be so distressing and interfere so much with a person's life that they can lead to 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 . People may develop a substance use disorder Substance Use Disorders Substance use disorders generally involve behavior patterns in which people continue to use a substance despite having problems caused by its use. The substances involved tend to be members... read more . People who have an anxiety disorder (except for certain very specific phobias Specific Phobic Disorders Specific phobic disorders involve persistent, unrealistic, intense anxiety about and fear of specific situations, circumstances, or objects. The anxiety caused by a phobic disorder can interfere... read more , such as fear of spiders) are at least twice as likely to have depression as those without an anxiety disorder. Sometimes people with depression develop an anxiety disorder.
Diagnosis of Anxiety Disorders
A doctor's evaluation, based on specific 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 look for other disorders that may be causing anxiety, such as 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 or a sleep disturbance Overview of Sleep Sleep is necessary for survival and good health, but why sleep is needed and exactly how it benefits people are not fully understood. One of sleep's benefits is its restorative effect on people's... read more . Doctors also ask whether relatives have had similar symptoms, because anxiety disorders tend to run in families.
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 appropriate
Psychotherapy
Drug therapy
Treament of other active disorders
Accurate diagnosis is important because treatment varies from one anxiety disorder to another. Additionally, anxiety disorders must be distinguished from anxiety that occurs in many other mental health disorders, which involve different treatment approaches.
If the cause is another medical disorder or a drug, doctors aim to correct the cause rather than treat the symptoms of anxiety. Anxiety should subside after the physical disorder is treated or the drug has been stopped long enough for any withdrawal symptoms to abate. If anxiety remains, antianxiety drugs or psychotherapy (such as behavioral therapy) is used.
For people who are dying, certain strong pain relievers, such as morphine Opioid Pain Relievers Pain relievers (analgesics) are the main drugs used to treat pain. Doctors choose a pain reliever based on the type and duration of pain and on the drug's likely benefits and risks. Most pain... read more , may relieve both pain and anxiety.
If an anxiety disorder is diagnosed, drug therapy 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. Benzodiazepines (such as diazepam) are commonly prescribed for acute anxiety. 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. Specific treatments depend on which anxiety disorder is diagnosed.
All of the anxiety disorders can occur along with other psychiatric conditions. For example, anxiety disorders often occur along with an alcohol use disorder Alcohol Alcohol (ethanol) is a depressant. Consuming large amounts rapidly or regularly can cause health problems, including organ damage, coma, and death. Genetics and personal characteristics may... read more . It is important to treat all of these conditions as soon as possible. Treating the alcohol use disorder without treating the anxiety is unlikely to be effective since the person may be using alcohol to treat 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 about Anxiety Disorders
National Institute of Mental Health, Anxiety Disorders: General information on many aspects of all the anxiety disorders, including crisis lines and educational programs
