Specific criteria include the presence of each of the following: Excessive anxiety and worry that patients have difficulty controlling Symptoms present on more days than not for ≥ 6 months Symptoms cause significant distress or impair functioning socially or at school In addition, the above criteria must be accompanied by ≥ 1 of the following: Restlessness or a keyed-up or on-edge feeling Being easily fatigued Difficulty concentrating Irritability Muscle tension Sleep disturbance Occasionally, generalized anxiety disorder can be confused with attention-deficit / hyperactivity disorder (ADHD) because generalized anxiety disorder can cause difficulty paying attention and can result in psychomotor agitation (ie, hyperactivity).