Objective: There is mounting evidence indicating that oxidative and inflammatory processes may have an important role in the pathogenesis of panic disorder (PD). PD is a heterogeneous disease, and panic attacks are divided according to the different symptom clusters as respiratory, nocturnal, non-fearful, cognitive, or vestibular subtypes. The aim of this study was to compare whole-blood and serum superoxide dismutase (SOD), glutathione peroxidase and adenosine deaminase activities in PD patients with/without nocturnal, respiratory subtypes and healthy subjects. Methods: The study was conducted including 60 patients with PD and 30 healthy control subjects. The Panic Attack Symptom Checklist, Panic and Agoraphobia Scale, Hamilton Depression Rating Scale and Hamilton Anxiety Rating Scale were administered to the patients. Biochemical analyses were performed after all the blood samples were collected. Results: We found that whole-blood SOD and glutathione peroxidase activities of patients were significantly lower and adenosine deaminase activities of patients were higher than those of healthy controls. There were no statistically significant differences between respiratory and nocturnal subtypes. In addition, there were no marked relationships between the duration of illness and panic-agoraphobia scores of patients with nocturnal subtypes. Hamilton Depression Rating Scale and Hamilton Anxiety Rating Scale scores of patients with the nocturnal subtype were markedly higher than those of patients without the nocturnal subtype. Conclusion: The results suggest that oxidative and inflammatory processes may play a role in the pathophysiology of PD. These findings may support the idea that both nocturnal and respiratory subtypes of PD have different symptom clusters of the same disease. Copyright (C) 2012 S. Karger AG, Basel