An evolutionary psychology explanation is that increased anxiety serves the purpose of increased vigilance regarding potential threats in the environment as well as increased tendency to take proactive actions regarding such possible threats. This may cause false positive reactions but an individual suffering from anxiety may also avoid real threats. This may explain why anxious people are less likely to die due to accidents.
Anxiety attacks, also called panic attacks, are episodes of intense fear and emotional distress that usually occur suddenly and without warning, and typically last from several minutes up to an hour. These attacks may have a discrete trigger, but they also can occur without any identifiable cause. Anxiety attacks are often recurrent, and are very distressing to the people who experience them, as well as their loved ones.
Fortunately, panic disorder is a treatable condition. Psychotherapy and medications have both been used, either singly or in combination, for successful treatment of panic disorder. If medication is necessary, your doctor may prescribe anti-anxiety medications, certain antidepressants or sometimes certain anticonvulsant drugs that also have anti-anxiety properties, or a class of heart medications known as beta-blockers to help prevent or control the episodes in panic disorder.
Social anxiety disorder (previously called social phobia): People with social anxiety disorder have a general intense fear of, or anxiety toward, social or performance situations. They worry that actions or behaviors associated with their anxiety will be negatively evaluated by others, leading them to feel embarrassed. This worry often causes people with social anxiety to avoid social situations. Social anxiety disorder can manifest in a range of situations, such as within the workplace or the school environment.