Antidepressant effect of prolonged twice-weekly intranasal esketamine treatments after nonresponse to electroconvulsive therapy in a patient with treatment-resistant depression.

Presents a case report of a woman with depressive episodes, which began in early 2019 and was worsened by the change of her long-standing antidepressant regimen of fluoxetine to mirtazapine. Subsequently, she received 12 right unilateral ultrabrief pulse electroconvulsive therapy (ECT) treatments without any benefit. She experienced no benefit from 4 additional trials of antidepressants and during our evaluations over several weeks, her mood remained severely depressed. After 6 treatments, she experienced >50% reduction in her depression. However, her esketamine treatments were paused for 8 weeks due to COVID-19. Her depression worsened and a 4-week-long course of twice-weekly treatments was initiated, which resulted in a >50% reduction in her depression. After switching to weekly maintenance treatments, her symptoms of low mood, anhedonia, and suicidal ideation returned to her pre-treatment baseline. As she had responded well to twice-weekly treatments, the frequency of treatments was increased. In summary, this patient responded to twice-weekly esketamine treatments, experienced symptomatic worsening after switching to weekly treatments, but was able to attain remission with prolonged twice-weekly treatments. (PsycInfo Database Record (c) 2022 APA, all rights reserved)