The lifetime prevalence of panic attacks is 28.3% in American adults 18 years and older. The age of onset of panic attack extends throughout adulthood; however, it typically develops in early adulthood, with median age of onset of 22 years [Kessler R.C., Chiu W.T., Jin R., Ruscio A.M., Shear K., Walters E.E. The epidemiology of panic attacks, panic disorder, and agoraphobia in the National Comorbidity Survey Replication. Arch Gen Psychiatry. 2006 Apr;63(4):415–24.]. As reported in our case, panic attacks could induce transient leukocytosis in healthy adults. If practitioners recognize this association, expensive investigations and extensive hospital stays may be prevented, although prudent practice would likely still require some type of investigations.