Potential effectiveness and safety of olanzapine in refractory panic disorder

Abstract

Panic disorder is a common and disabling psychiatric disorder. Despite treatment advances, refractory panic disorder requires novel interventions. One such pharmacologic intervention with theoretical and case study support includes olanzapine, a thienobenzodiazepine medication currently approved for schizophrenia in the United States. Ten people with refractory DSM-IV diagnosed panic disorder completed an 8-week, open-label, flexible-dose clinical trial. Baseline, in-treatment, and end-of-treatment data for panic attacks, anticipatory anxiety, phobic avoidance, and impairment were collected. Data were analyzed using SPSS software. Refractory panic disorder patients required a wide dose range averaging 12.3 mg/day of olanzapine to significantly improve or ablate panic attacks. On the average, number of attacks decreased from 6.1/week at baseline to 1.1/week at the end of treatment, and anticipatory anxiety from 32% of the day to 8% of the day. At treatment end, 5 of 10 participants (50%) were panic free, 4 (40%) had one attack in the previous week, 1 (10%) had seven attacks in the previous week, and 6 of 10 participants (60%) were anticipatory anxiety free. There were also statistically and clinically significant improvements in impairment over the course of the trial. There were no significant changes in vital signs, emergent side effects, or average weight, although 6 of 10 people did gain weight. Olanzapine is potentially effective and safe in panic disorder. Due to study limitations, further clinical trials are needed to demonstrate effectiveness.

Canadian clinical practice guidelines for the management of anxiety, posttraumatic stress and obsessive-compulsive disorders

“…Atypical antipsychotics: There is some evidence that atypical antipsychotics may have some benefits in the treatment of patients with refractory panic disorder [217,267,268]. In a RCT, risperidone monotherapy was as effective as paroxetine (Level 2) [217].…”

“…In a RCT, risperidone monotherapy was as effective as paroxetine (Level 2) [217]. Open-label data also support the use of risperidone [267], olanzapine [268], and quetiapine [267]. There are also open-label data supporting the use of some atypical antipsychotics as adjunctive therapy (see below).…”

Comorbid Anxiety in Bipolar Disorder Alters Treatment and Prognosis

“…These include the anticonvulsant gabapentin (for social phobia and panic disorder, [81,82]), and the second generation antipsychotics olanzapine and quetiapine (for panic disorder, OCD, nonspecific anxiety symptoms, and perhaps PTSD, [83][84][85][86][87][88]). Primary mood stabilizers may also have an effect but have not been as extensively studied (e.g., PTSD, panic disorder, [89]).…”

Advances in the Management of Treatment-Resistant Anxiety Disorders

“…There is only preliminary positive evidence for some second-generation antipsychotics. Two open-label studies have examined olanzapine monotherapy (47) and olanzapine augmentation after a failed SSRI trial (48) with positive results. Risperidone augmentation appeared to be effective for panic disorder that had not responded to an SSRI and/or benzodiazepine in a small 8-week open-label study (Nϭ30) (49).…”