Generalized anxiety disorder is an anxiety disorder which consists of excessive and irrational worry of everyday things. This worry tends to interfere with normal daily functioning: people who have GAD anticipate disasters and they're always concerned about health matters, money, death, their own futures or family trouble. Physical issues include though are not limited to trembling, numbness, muscle tension, sweating or hot flashes for at least six months. Between six and eight million American adults have GAD.