Anxiety may be that feeling you get before speaking in front of a large audience. Or it may be terror that stops you in your tracks. There are different types of anxiety disorders affecting millions of people. According to a 2005 report in the Archives of General Psychiatry about 40 million American adults over 18 years old experience anxiety disorders in a given year. While some anxiety may be typical for most people, anxiety disorders last at least 6 months and they’re commonly present with other mental or physical illnesses. Types of anxiety disorders include generalized anxiety disorder, panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, social anxiety disorder, and specific phobias. Research is ongoing as to what causes an anxiety disorder - scientists say they are probably the result of genetic, environmental, psychological and developmental factors. Treatment usually involves the use of medication, psychotherapy or both. Watch more video about anxiety or share your story on video with icyou.