People with generalized anxiety disorder have recurring fears or worries, such as about health or finances, and they often have a persistent sense that something bad is just about to happen. The reason for the intense feelings of anxiety may be difficult to identify. But the fears and worries are very real and often keep individuals from concentrating on daily tasks.
Someone who suffers severe physical or emotional trauma such as from a natural disaster or serious accident or crime may experience post-traumatic stress disorder. Thoughts, feelings and behavior patterns become seriously affected by reminders of the event, sometimes months or even years after the traumatic experience. Symptoms such as extreme fear, shortness of breath, racing heartbeat, insomnia, nausea, trembling and dizziness are common in these anxiety disorders. Although they may begin at any time, anxiety disorders often surface in adolescence or early adulthood. There is some evidence that anxiety disorders run in families; genes as well as early learning experiences within families seem to make some people more likely than others to experience these disorders.