Management of treatment-refractory panic disorder

Treatment resistance remains a relatively common problem in panic disorder (PD) despite the success of the selective serotonin reuptake inhibitors (SSRIs) and cognitive behavioral therapy (CBT) as first-line agents. Factors contributing to medication treatment resistance include inadequacy of trial duration, improper dosage, poor tolerability, noncompliance, and medical and psychiatric comorbidity. Poor tolerability to the SSRIs can frequently be addressed by judicious lowering of the initial dose, with a gradual upward titration. For patients who have not responded to one or more adequate trials of SSRIs, options include combination treatment with a benzodiazepine or tricyclic antidepressant (TCA), augmentation with pindolol, or switching to a different class of medication. The newer antidepressants, particularly venlafaxine XR, seem promising as alternatives, and might be beneficial for the refractory patient with a comorbid mood disorder. Anticonvulsants and olanzapine might be particularly beneficial for the refractory patient with hypomania, irritability, and insomnia, who also has demonstrated acute SSRI hypersensitivity. Experimental therapeutics in refractory panic probably will continue to examine the role of corticotropin releasing factor and glutamate/GABA systems. The role of CBT in the medication refractory patient has been explored, with preliminary suggestions of efficacy.