Phobias are constant, irrational fears that afflict some people. Their fear should be taken seriously. The person should never be made fun of or belittled because of their fear. But, as writers, we can bless (or curse) our characters with phobias and make the story so much more interesting.
What happens if someone encounters the object of their fear? They could feel dread, nausea, or breathlessness. They could sweat excessively or lose the ability to think or speak clearly. They could lose control and become angry. Detachment from reality is a possibility, as is a full-blown anxiety attack.
Pick one of the following phobias – alliumphobia, anthrophobia, illyngophobia, oneirophobia – and see if you can create a character with that specific fear.
Alliumphobia is the fear of garlic. I guess that the people afflicted with this phobia just aren't afraid of vampires at all; they are afraid of garlic in any form. Those with alliumphobia don't want to see garlic, they don't want to smell garlic, and they most definitely don't want to eat any garlic. You woud not want to take a person with this phobia out to an Italian restaurant (or just about any other restaurant, either) nor would this person want to eat at my house. Garlic is added to most everything I cook.
If you create a character with this phobia, where would he live? What would he eat? How would this phobia affect his social and personal life?
Oh, yeah, people with alliumphobia also usually react with panic and anxiety when confronted with such inane things as the opinions or beliefs of other people.
Anthrophobia or anthophobia is simply the fear of flowers. Flowers are beautiful and I can't imagine being afraid of them, but a person afflicted with anthrophobia is deathly afraid of them. Maybe this fear would stem from some horrific incident in his or her life that involved flowers.
How would your character with anthrophobia react if he or she were locked inside a flower shop or greenhouse?
Illyngophobia is not just a fear of heights, it is the fear of becoming dizzy when looking down from high up. Vertigo is the feeling you get when you become dizzy from looking down. There are actually two different forms of vertigo, objective vertigo and subjective vertigo. In objective vertigo, you feel as though objects are spinning around you. In subjective vertigo, you feel as though you are moving or swaying. It may be fun to create a character that has both objective and subjective vertigo. I'm not sure that actually happens, but it could happen on paper.
Oneirophobia is the fear of dreams. I guess if one frequently had nightmares or horrible dreams, a person would tend to be scared of dreaming. I can see a person with oneirophobia going into a panic attack when and if a dream begins, as he or she would be asleep and unable to distract himself from it in any way. If one's own nightmares aren't the cause of this phobia, maybe movies such as “Nightmare on Elm Street” and its sequels could somehow have caused this fear.

