In this article, we describe the treatment of a patient with bipolar affective disorder, which was complicated by an underlying obstructive sleep apnea (OSA). The patient's underlying OSA made pharmacological intervention complicated and actually led to respiratory failure. Moreover, her manic psychosis proved to be resistant to treatment. Eventually, electroconvulsive therapy (ECT) was effectively used to control her manic psychosis. This case highlights the importance of screening for OSA due to the complications of psychotropic medications in this context. The pre- and post-electroconvulsive therapy management in the setting of the comorbidity of bipolar affective disorder and OSA is also described as part of this case report.