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I am a Japanese man. My wife has been diagnosed as bilpoar disorder for over 10 years.I read  Bipolar disorder a cognitive therapy approach  interestingly.A rapid cycling becomes the topic of conversation at the Japanese website.According to the book  Bipolar disorder a cognitive therapy approach , a rapid cycling is being explainedwith Some bilpoar patients display four or more cycles within a year and are therefore categorized as  rapid cyclers.  According to the DSM-4, at least 4 days of hypomania or mania and 2 weeks of depression are required to qualify as a cycle. .For my understanding, I do not see any mistake for this article. However one of  my friendsinsists that the cycle of  twice a year is enough for a rapid cycling. APA is explaining   In DSM-IV, rapid cycling is defined as the occurrence of at least four major depressive, manic, hypomanic, or mixed episodes during the previous year, demarcated either by a remission of at least 2 months' duration or by a switch to an episode of opposite polarity, e2€œbut what kind of meaning is this?I am confused about rapid cyclers.  I hope you could explain more details about rapid cycling clearly.   I am appreciated for your help. arigato   teruaki