I thought this short discussion of the two kinds of anxiety and D was helpful. It is from the Northwester University Med school site.Anxiety DisordersWhat are anxiety disorders?Anxiety is a natural response, one that moves our body toward fight, fright , or flight in response to immediate threats. But in the case of more than 25 million Americans, anxiety is a constant response to everyday events, one of apprehensions, uncertainty, and fear. Anxiety disorders can be symptomatic of other problems such as depression, drug abuse, or serious medical conditions, but in many cases anxiety disorders exist with no precursor.Many types of anxiety disorders exist, but two main types are common. Generalized anxiety disorder (GAD) can be described as a constant state of tension and anxiety lasting for at least six months. People have impaired normal functioning due to feeling on edge, fatigue, inability to concentrate, irritability, and sleep disturbances. Like all other types of anxiety, a rise in blood pressure is common, as well as rapid breathing, increase in muscle tension, nausea, and diarrhea. Panic disorder, the other main type of anxiety disorder, manifests in periodic attacks of anxiety or terror, usually lasting 15 to 30 minutes. People experience sweating, shakiness, shortness of breath, dizziness, nausea, feeling of unreality, and fear of dying or going insane. The attacks occur in any number of patterns and be spontaneous or in response to specific stressors. Other anxiety disorders include phobias, obsessive-compulsive disorder, and post-traumatic stress disorder.Genetics, biochemistry, environmental factors, and psychological stress all interact in the development of anxiety disorders. Usually panic disorders develop in late adolescence, while GAD can occur at any age. Women are affected more than men. Anxiety disorders can mimic symptoms of other conditions like heart attacks so physicians must perform comprehensive examinations in diagnosing the disorders. Those with anxiety disorders are at risk for suicide, depression, and substance abuse, and their disorder can have an adverse effect on physical health and relationships.Most anxiety disorders respond well to treatment. A common and effective method of treatment currently is a combination of cognitive-behavioral therapy with medication. Many anti-anxiety and antidepressant medications are available for those suffering from anxiety disorders, and research continues to uncover more alternatives everyday.