Feeling anxious is normal in particularly stressful situations. However, if the anxiety is out of proportion to the situation, or persists when the stress that originally triggered it has passed, or the anxiety appears for no logical reason, then it becomes a problem which can affect your everyday life.
Stress can come and go as the external factors causing it (be it work, relationships or money problems, etc.) come and go, but anxiety can persist, whether or not the cause is clear to the sufferer.
Sometimes the cause of the anxiety is easy to identify, such as a traumatic incident or a significant life event (getting divorced, being made redundant). However, when there is no identifiable cause for the anxiety it can be very distressing, because you live in fear, unsure when it's going to affect you. This explains why sometimes the anxiety can seem to come out of the blue with no apparent trigger.
If something distressing happened to you in the past, or you were in a situation which caused you significant anxiety, and you were unable to deal with your emotions at the time, you may become anxious about facing similar situations again in case they stir up the same feelings of distress. This then automatically triggers an anxious response, which becomes habitual whenever you are in similar situations in future.
At a conscious level, you may well know that your reaction to certain situations is illogical, but the subconscious doesn't apply logic to the situation. It just reacts in the way it's been trained to react.
Feelings of fear caused by anxiety can overwhelm you and can lead to panic attacks, which can be very frightening for the sufferer, and the fear of having a panic attack only serves to make it more likely to happen again. It becomes a self-fulfilling prophecy. Sometimes the anxiety can be so debilitating it affects your everyday life, or stops you from doing things that most people take for granted, or can even make you afraid to leave your home.
How does it work?
The approach will vary depending on each individual's specific requirements, but it very loosely involves changing the automatic conditioned response in the subconscious mind that causes you to respond to certain triggers. This is something that many people cannot control through conscious thought processes because, when behaviours are so deeply ingrained in the subconscious, changes often can't be implemented at a conscious level.
Under hypnosis, the learned anxious response within the subconscious can be changed to something more appropriate to the situation, so that in future, you will be calm, relaxed and in control in the situations that used to cause you anxiety.