Both depression and panic disorder are found commonly in community surveys and it is not unexpected that there should be a cooccurrence of these disorders in some patients. However, recent data suggest that there is a greater clustering of depression among panic disorder patients and panic disorder among depressed patients than one might expect by chance alone. For example, further analysis of data from the National Comorbidity Survey indicates that there is a history of major depression in 55.6 % of subjects with lifetime panic disorder and that 21.6 % of depressed patients experience a panic attack at some time in their lives. The high incidence of comorbidity of panic and major depressive disorders emphasizes the value of pharmacotherapy with a broad-spectrum agent that can treat the symptoms of comorbid psychiatric disorders effectively. Of the therapeutic options available, there is mounting evidence that selective serotonin reuptake inhibitors (SSRIs) represent reasonable monotherapy for patients with comorbid depression and panic disorder, based on the equivalent efficacy and improved side-effect profiles compared with other classes of antidepressant. The clinical relevance of differences in the pharmacokinetic and clinical profiles of SSRIs have been discussed in the context of treatment strategies for the patient with comorbid depression and panic disorder.