Shortness of breath, choking or smothering sensations, chest pain or discomfort, and fear of dying. Due to the coronavirus disease 2019 (COVID-19) pandemic, our minds have been conditioned to associate these symptoms with a rather severe form of the disease. Although such symptoms could indicate a case of COVID-19, they are also common in panic attacks (PAs)(ie, the hallmark of panic disorder [PD]), in which respiratory symptoms occur along with other panic symptoms that are mainly physical in nature. 1, 2

Experimental evidence has supported the hypothesis, unique in the realm of mental disorders, that subclinical alterations of basic physical functioning, mainly the respiratory system, may be involved in the pathogenesis of PAs. Patients with PD were thought to have a hyperactive suffocation alarm, which results in a specific behavioral and respiratory hypersensitivity to hypercapnia. Different laboratory challenges that induce hypercapnia (eg, the Read’s rebreathing technique, the prolonged inhalation of 5% or 7% of CO2-enriched air, and the double inhalation of a 35% CO2 and 65% O2 gas mixture) resulted in higher rates of PAs and respiratory-response abnormalities in PD patients than controls. Moreover, these patients are hypersensitive to various other laboratory respiratory challenges, such as breath-holding, hyperventilation, and a hypoxic challenge test. 1, 2 They suffer from irregular breathing patterns, impaired diaphragmatic breathing with reduced vital capacity, chronic hyperventilation, and a common sensation of difficulty in breathing during activities of daily living. 3 Finally, PD has remarkable associations with asthma or chronic obstructive pulmonary disease. PD patients also have imbalanced autonomic regulation, reduced heart rate variability, poorer cardiovascular fitness, and higher variability of electrocardiographic QT interval and cardiac repolarization. 2 Although the source of these features is still unclear, patients with PD experience, from a clinical point of view, a significant burden of respiratory and physical symptoms or discomfort during PAs, as well as in certain environmental situations. Furthermore, the fear of suffocation is one of their primary troubles. Overall, they seem to exhibit