However, there are millions of people who experience a high level of anxiety on a continuous basis and for no apparent reason. This anxiety disorder can include panic attacks, generalized anxiety disorder (GAD)and obsessive-compulsive disorder (OCD). 

The first sign of an impending panic attack is usually a shortness of breath with chest pain or tightness. The attack comes on suddenly, with an unexplained and uncontrollable feeling that has been best described as inner terror. The one having the attack often think they are dying. They become convinced they are having a heart attack or are on the verge of losing all control. 

This intense fear normally reaches its peak within 10 minutes, with a variety of symptoms following the onset. A person may experience trembling, heart palpitations, hyperventilation, hot or cold flashes, sweating, dizziness, nausea, burning sensations in the face or neck, tingling or numbing in the entire body, tunnel vision or a feeling of being detached from reality. Their panic leads to fear, which leads to increased anxiety, causing the panic to escalate. This cycle is extremely difficult to get through and is very frightening, especially to a first-time sufferer. The aftereffects can last hours or longer. It could be several days before a person begins feeling "normal" again. 

The main difference between panic attacks and other anxiety disorders is their intensity and separate episodes that occur without warning. Panic attacks may also lead to a social anxiety disorder or a social phobia. People with social anxiety often restrict or minimize social interactions to avoid suffering the embarrassment of their excessive anxiety or of having a panic attack in front of other people. 

Generalized anxiety disorder is a consistent worrying or tension without cause. Usually, someone with GAD constantly jumps from one stressful thought to another and cannot stop the torment. 

Symptoms of GAD can include trouble concentrating, feelings of dread, irritability, depression, restlessness, being easily startled, and sleep disorders like insomnia and bad dreams. Behavioral effects may occur, such as withdrawal from anxious situations, nail biting, foot tapping, self-medication leading to substance abuse and obsessive-compulsive disorder. 

The physiological well-being of a person can be affected in many adverse ways by severe anxiety lasting more than a few months. They may experience otherwise unexplained signs, such as heart palpitations, high blood pressure, elevated heart rate, weakness, tense muscles, extreme fatigue, nausea, diarrhea and cramps, chest pains, breathing difficulties, or headaches. 

Many anxiety disorders are manageable with antidepressants, regular exercise, a healthy diet or various therapies such as cognitive-behavioral therapy. It is worth it to learn what remedy works best for the individual who suffers with anxiety that is extreme enough to interfere with daily life and contentment.