Phenomenology of panic attacks: responsiveness of individual symptoms to imipramine

A number of studies have demonstrated that individual panic symptoms are not equivalent vis-a-vis their clinical salience. This study investigated the proposition that individual panic symptoms may also differ in their specific responsiveness to treatment in 63 patients with panic disorder with agoraphobia who had completed an 8-week placebo-controlled dose-ranging study with imipramine. The results revealed that fear, unreality, and respiratory symptoms, most strongly dyspnea and choking, displayed the highest degree of early differentiation between effective and ineffective doses of the drug, whereas palpitations, tingling, and sweating had the most pronounced effects between weeks 4 and 8 of treatment. On the other hand, the symptom of hot and cold flashes did not differ between adequate and inadequate treatment. The evidence presented reinforces the notion that individual panic symptoms are not functionally equivalent and suggests that some symptoms, in particular fear, derealization, and the respiratory symptoms, may be more central than others to the therapeutic process just as some of them have been found to be more important for diagnostic considerations. The results are briefly discussed from the methodologic and phenomenologic perspectives.