Abstract: Catatonia, associated with a variety of medical and psychiatric conditions such as mood disorders and schizophrenia, is frequently treated with either benzodiazepines or with electroconvulsive therapy (ECT) in treatment-resistant cases. Simultaneous treatment with both is usually avoided. Here, we report a case of the use of the benzodiazepine antagonist flumazenil before ECT to facilitate the simultaneous use of lorazepam and ECT for the treatment of co-occurring catatonia and obsessive-compulsive disorder. Both catatonia and obsessive-compulsive disorder symptoms improved in the patient. Physicians should be aware of flumazenil as a clinical tool for use in treatment-resistant cases.