The best replacement for rapid cycling is mixed state.

The best alternatives to rapid cycling are rated as following:
★★★★★  mixed state
★★★★  mixed episode
★★  cyclothymia

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Speaking about rapid cycling, one probably shouldn't forget about bipolar.

Other search terms related to rapid cycling and their ratings are:
★★★★★ bipolar
★★★★ bipolar disorder
You have in mind a companion for rapid cycling and it is not yet here? Propose!



Google Trends

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rapid cycling
mixed state
mixed episode