Anxiety is a general term for several disorders that cause nervousness, fear, apprehension, and worrying.

These disorders affect how we feel and behave and can cause physical symptoms. Mild anxiety is vague and unsettling, while severe anxiety can seriously affect day-to-day living.

Anxiety disorders affect 40 million people in the United States (U.S.). It is the most common group of mental illnesses in the country. However, only 36.9 percent of people with the condition receive treatment.

What is anxiety?

The American Psychological Association (APA)defines anxiety as “an emotion characterized by feelings of tension, worried thoughts and physical changes like increased blood pressure.”

It is important to know the difference between normal feelings of anxiety and an anxiety disorder that requires medical attention.

Anxiety

When faced with potentially harmful or worrying triggers, feelings of anxiety are not only normal but necessary for survival.

Ever since the earliest days of humanity, the approach of predators and incoming danger has set off alarms in the body and allowed an individual to take evasive action. These alarms become noticeable in the form of a raised heartbeat, sweating, and increased sensitivity to surroundings.

A rush of adrenaline in response to danger causes these reactions. This adrenaline boost is known as the ‘fight-or-flight’ response. It prepares humans to physically confront or flee any threats to safety.

For most modern individuals, running from larger animals and imminent danger is a less pressing concern. Anxieties now revolve around work, money, family life, health, and other crucial issues that demand a person’s attention without necessarily requiring the ‘fight-or-flight’ reaction.

That nervous feeling before an important life event or during a difficult situation is a natural echo of the original ‘fight-or-flight’ reaction. It can still be essential to survival – anxiety about being hit by a car when crossing the street, for example, means that a person will instinctively look both ways to avoid danger.

Anxiety disorder

The duration or severity of an anxious feeling can sometimes be out of proportion to the original trigger, or stressor. Physical symptoms, such as increased blood pressure and nausea, may also become evident. These responses move beyond anxiety into an anxiety disorder.

Anxiety disorders occur when a reaction is out of proportion to what might normally be expected in a situation. The APA describes a person with anxiety disorder as “having recurring intrusive thoughts or concerns.”

Types

Anxiety disorders can be classified into six main types. These include:

Generalized anxiety disorder (GAD): This is a chronic disorder involving excessive, long-lasting anxiety and worries about nonspecific life events, objects, and situations. It is the most common anxiety disorder. People with GAD are not always able to identify the cause of their anxiety.

Panic disorder: Brief or sudden attacks of intense terror and apprehension characterize panic disorder. These attacks can lead to shaking, confusion, dizziness, nausea, and breathing difficulties. Panic attacks tend to occur and escalate rapidly and peak after 10 minutes. However, they may last for hours.

Panic disorders usually occur after frightening experiences or prolonged stress but can also occur without a trigger. An individual experiencing a panic attack may misinterpret it as a life-threatening illness. Panic attacks can also lead to drastic changes in behavior to avoid future attacks.

Phobia: This is an irrational fear and avoidance of an object or situation. Phobias differ from other anxiety disorders, as they relate to a specific cause. The fear may be acknowledged as irrational or unnecessary, but the person is still unable to control the anxiety. Triggers for a phobia may be as varied as situations, animals, or everyday objects.

Social anxiety disorder: This is a fear of being negatively judged by others in social situations or a fear of public embarrassment. This includes a range of feelings, such as stage fright, a fear of intimacy, and a fear of humiliation. This disorder can cause people to avoid public situations and human contact to the point that everyday living is rendered extremely difficult.

Obsessive-compulsive disorder (OCD): This is an anxiety disorder characterized by thoughts or actions that are repetitive, distressing, and intrusive. OCD suffers usually know that their compulsions are unreasonable or irrational, but they serve to alleviate their anxiety. People with OCD may obsessively clean personal items or hands or constantly check locks, stoves, or light switches.

Post-traumatic stress disorder (PTSD): This is anxiety that results from previous trauma such as military combat, sexual assault, a hostage situation, or a serious accident. PTSD often leads to flashbacks, and the person may make behavioral changes to avoid triggers.

Separation anxiety disorder: This is characterized by high levels of anxiety when separated from a person or place that provides feelings of security or safety. Separation sometimes results in panic symptoms. It is considered a disorder when the response is excessive or inappropriate after separation.