Not necessarily. Studies have shown that approximately 10 percent of patients have a single episode only. However, the majority of patients have more than one. The number of episodes within a patient’s lifetime varies. Some individuals may have only two or three within their lifetime while others may have the same number within a single year. Frequency of episodes depends on many factors including the natural course of the condition as well as on appropriate treatment. Not taking medication or taking it incorrectly are frequent causes of episode recurrence.