There are different triggers of social anxiety. The first cause has to do with genetics. If one or both parents have social anxiety disorder, chances are one, or some of their children will have it too. Stressful life experiences, such as bullying, rejections, abuse, or teasing, are also known to be triggers of social anxiety.
Health conditions that draw attention to a person's appearance, such as skin conditions, eye problems, or physical disabilities, could also trigger social anxiety. Doctors diagnose social anxiety from a description of the symptoms and after assessing certain behavioral patterns.