The fear of heights is one of the most common anxieties or phobias in the world. Like most phobias, it has a special name, Acrophobia. Acrophobia is commonly confused with Agoraphobia because of the similarity in names. But Agoraphobia is actually a fear of wide open spaces and areas where an individual lacks control. Interestingly many agoraphobics are also, as part of the same condition Acrophobic or scared of heights. This is probably due to the fact that high buildings and skyscrapers, as well as cliff tops, have limited easy exit routes. This lack of control is often important to the Agoraphobic.
Also, the fear of heights is often called Vertigo. This is completely wrong. Vertigo is symptomatic of inner ear disorders and other medical problems associated with balance. It often includes feelings of dizziness, swaying or spinning and can occur anywhere, not just at height. Interestingly it seems that some people suffering from anxiety disorders such as agoraphobia and panic attacks may be predisposed to balance disorders. In a British Medical Journal (BMJ) editorial entitled: Treating dizziness with vestibular rehabilitation it is stated that "On the other hand, recent research indicates that panic and agoraphobia may often be triggered by an underlying dysfunction of balance." It suggests that the effect of balance issues such as dizziness may lead to anxiety is patients that believe their symptoms are down to brain tumours or other serious health problems. In these cases vestibular rehabilitation (basically exercises to improve the functioning of the balance mechanism) may be beneficial in reducing dizziness and anxiety or panic symptoms associated with it.
Many people have a fear of heights that stops them looking strait down from balconies or directly over cliffs. For the most part this kind of fear is appropriate and normal and does not really infringe on quality of life. When it gets more serious than this, i.e. when people are unable or unwilling to do the things they want or need to do in their daily life (like work in an office block, for instance) some action needs to be taken.
It is worth investigating whether any physical problems exist with your balance mechanism in the inner-ear. It is my personal belief, although not established medical fact as far as I am aware, that looking at things from a height may cause disorientation in people with poor balance mechanisms as there is little with which to reference the height.
Apart from that, if this is a simple phobia, i.e. if this is your only phobia, then a course of cognitive and behavioural therapy will probably serve you best. Graded exposure with healthy thought processes can probably much improve the problem. After all, you are very unlikely actually to be in real danger of falling in an office block!
Other therapies such as flooding exist, but I don’t particularly recommend them!