Do you avoid getting on a plane, even though you get in cars all the time and know your chances of dying in a car accident are much higher? Do you drive miles out of your way to avoid going over a bridge? Do thunderstorms make you feel panicky, even though no harm has ever come to you during a storm? Are you so afraid of medical procedures that you haven't seen a doctor in years?
Experiencing some fear in life is common. But when the fears are not rational and they interfere with your life, the fear is more likely a phobia. It's not actually diagnosed as a phobia unless:
The fear is excessive or unreasonable.
Being exposed to the fearful situation or object causes a feeling of anxiety, which may become a panic attack. (See this month's article about panic attacks )
You recognize that the fear is unreasonable.
You either avoid the feared activity or object or you endure it with intense anxiety and distress.
The avoidance or anxiety interfere with your normal routine, job, school work or social relationships, or you are highly upset about having the fear itself.
How exactly would you define a fear that is disruptive to your normal routine? Let's say you get a job promotion to a position that requires you to travel regularly. You're thrilled with the prospect of increasing your responsibilities and making more money. But you're afraid of flying so you turn down the position. Or you're so afraid of getting an injection or having a medical procedure that you completely avoid going to the doctor or dentist. These are examples of ways that a phobia could be interfering with your life.
Two kinds of phobias  specific  and "social" Phobias are generally classified into two types, "specific phobia" and  social phobia.  Social phobia is a fear of social situations or "performance situations" (such as public speaking). People with social phobia are afraid that they'll be embarrassed in front of other people, or that others will judge them as anxious, weak, crazy or stupid.
Children who have social phobia are often extremely timid in unfamiliar social settings. They may avoid contact with other children, refuse to play in a group and often try to stay close to familiar adults.
Common traits of people with social phobia include
Being extremely sensitive to criticism
Having trouble being assertive
Having low self-esteem
They may be underachievers in school because they're afraid of taking tests or participating in class. As adults, they may not do as well as possible at work because they're afraid of speaking in groups, to the public or with supervisors and colleagues.
It's common for some people to confuse social phobia with shyness, but they're two different things. Shy people don't always experience severe anxiety in social situations, and they don't always avoid social situations. They're just generally shy in most situations. People with social phobia usually feel at ease with people most of the time. The anxiety is triggered only in certain situations.
The "specific phobia" category can include several different types, including:
Animal type: A fear of animals or insects. This type usually begins in childhood.
Natural environment type: Fear of things like storms, heights or water. This type also often begins in childhood.
Blood-injection-injury type: Fear of seeing blood or an injury, or of having an injection or other medical procedure. This type of phobia is most likely to cause fainting episodes.
Situational type: Fear of tunnels, bridges, elevators, driving, etc.
It's not uncommon for someone to have more than one type of phobia. And people who have a phobia in one subtype have an increased chance of having another phobia within that same type. For example, someone with an animal type phobia could have a fear of snakes and cats.
What are the causes? Nobody knows for sure exactly what causes specific phobias. Experts believe that some of the causes might include:
Experiencing traumatic events directly related to the phobia, such as being attacked by an animal.
Seeing other people experiencing trauma or demonstrating fear.
Having an unexpected panic attack when in the presence of the feared object or situation. For example, if you're riding in an elevator and you have a panic attack that's unrelated to the elevator ride, there's a chance you could eventually develop a fear of elevators.
Hearing constant warnings about certain situations or objects. Having a parent who constantly talks about the dangers of plane crashes, for example, could cause a child to develop a fear of airplanes later in life.
Phobias: common psychiatric conditions Phobias affect about 12 percent of all Americans. They are the most common psychiatric condition for women and the second most common for men.
Mental health professionals take phobias extremely seriously, and people who suffer from phobias have an excellent chance of overcoming their fears if they get the proper treatment. Behavioral therapy and cognitive therapy have produced excellent results for many people who have phobias. Some less conventional treatments, such as a type of hypnotherapy called eye movement desensitization and reprocessing, or EMDR, have also worked well for some people.
It can be difficult to seek treatment for phobias because you realize that your fear doesn't seem to make sense. But that's precisely what makes it a phobia, and your health care provider knows that. Getting rid of a phobia, or at least learning how to minimize your fear, helps you feel like you're  getting your life back.  Source: The American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Washington, D.C., 2000; H. Kaplan, B. Sadock, J. Grebb, Synopsis of Psychiatry, Williams and Wilkins, 1994; The National Mental Health Association.