While most people do not fault while having an anxiety more often then not they fear of fainting. This fear can cause even more anxiety which in turn intensifies the anxiety and symptoms of anxiety attacks. The rise in blood pressure a person experiences while under a panic or anxiety attack is what causes a person to feel light headed or some times dizzy as if they are going to faint. Even if a person has never failed during an anxiety attack the fear is more real then the reality of the situation. Controlled breathing can help to reduce these types of symptoms and simple distraction techniques to further calm a persons fears.
The most common form of anxiety causes people to breath faster which most likely will not cause you to fault however there are cases when a person has vasovagal syncope. This is a type of anxiety which causes a person to stop breathing. Most often associated with a blood or injury phobia a person will freeze up at the sight of blood or injures and stop breathing. The lack of oxygen to the brain is what causes people to faint. This form of anxiety is much rarer.
In even rarer cases people who do not experience vasovagal syncope may cause them selves to false just by making it so real in their mind that they actually do fault. In these cases distraction techniques must be practiced regularly in order to achieve a more clam state. Not practicing these techniques could cause injury to the person under attack during a false spell.