Patient reports and laboratory tests support the notion that panic attacks are generated by stimulation of brainstem nuclei. Scalp-recorded brainstem auditory evoked potentials may serve as a unique measurement strategy for the noninvasive assessment of the role of brainstem functioning in panic disorder. Ipsilateral and contralateral BSAEP recordings were examined in response to separate left and right ear click stimulation in 28 patients with a diagnosis of panic disorder and in 18 normal controls. Latency measures did not differentiate between the patient and control groups but amplitudes of wave III and V were found to be larger in patients. These findings are discussed in relation to pathophysiological and neurochemical theories of panic and specific emphasis is placed on serotonergic function.