This psychological reaction causes many physical symptoms. Some symptoms include shaking, rapid heartbeat, difficulty breathing, sweating, chest pains, dizziness, and a feeling of overwhelming anxiety. When a person has such physical reaction to something they fear, they are said to be having a panic attack.
People with phobias feel such great distress when they encounter the thing they fear that they go out of their way to avoid such an encounter. People with phobias often know that their fears are irrational, but feel completely unable to control their fears. Sometimes a phobia has only a minimal impact on a sufferer's life. For example, Janet Acra has a paralyzing fear of spiders ( arachnophobia).