Objectives This study revised the Korean Medication Algorithm Project for Bipolar Disorder2018 for rapid cycling. Methods Questionnaires to survey the expert opinion of medication for rapid cycling were completed by a review committee consisting of 87 Korean expert psychiatrists. The experts’ opinions ere classified into three categories based on the lowest category in which the confidence interval fell (6.5≤ for first-line, 3.5≤ for second-line, and 3.5> for third-line treatment). Results The first-line treatments were a combination of mood stabilizers and atypical antipsychotics, atypical antipsychotics monotherapy, or mood stabilizer monotherapy. Furthermore, amood stabilizer with lamotrigine therapy and an atypical antipsychotic with lamotrigine combinations was the first-line treatment for a depressive episode. The first-line medications in all episodeswere valproate, lithium, quetiapine, olanzapine, and aripiprazole. Risperidone was the first-linemedication in manic episodes and mixed states, and lamotrigine was the first-line medication fortreating depressive episodes. Conclusion Compared to the surveys in 2018, the preference for atypical antipsychotics andlamotrigine has increased, and the modalities as a second-line treatment are more diversified.