Rapid Cycling in Bipolar Disorder is quite common, affecting 10-20% of people with bipolar disorder, and typically affects more women than men. The name rapid-cycling refers to the number of episodes a person with bipolar disorder has over the course of one year. To be diagnosed as having rapid cycling bipolar disorder, a person must have at least four episodes over the course of twelve months. Often, though, people with rapid cycling bipolar disorder will experience very rapid shifts between mania, depression and mixed states. Some people may experience monthly, weekly or even daily shifts in mood. Weekly and daily shifts in mood are known respectively as ultra-rapid-cycling and ultra-ultra-rapid-cycling.
It can be extremely difficult to live with rapid-cycling bipolar disorder. Many people with this form of bipolar disorder have very few periods of normality in between their episodes and this can be very distressing. Switching rapidly between one mood state and the next leaves little chance for recovery between episodes.
Additionally, because of the rapid shifts between mood states, people with rapid cycling bipolar disorder may be more prone to partaking in risky behaviour and self-medication with drugs and alcohol.
Rapid cycling bipolar disorder is often more difficult to treat. Lithium, one of the main medications used to treat bipolar disorder, is rarely effective in rapid cycling, although other mood stabilising medications may be able to reduce the number of episodes a person has.