Case: Contrast medium-induced transient leukopenia is very rare. Here, we report a case of a 73-year-old man diagnosed with contrast media-induced transient leukopenia. The patient underwent abdominal contrast-enhanced computed tomography, where he was given non-ionic iodinated contrast medium i.v. His medical history included an allergic reaction to a different contrast medium. One hour later, the patient was admitted to the emergency department complaining of chest discomfort. He had leukopenia and a fever (temperature of 38.9°C). Complete blood count showed a white blood cell count of 930/μL and an absolute neutrophilic count of 232/μL.
Outcome: The patient was given i.v. antibiotics and 5 mg chlorpheniramine maleic acid, 20 mg famotidine, and 125 mg methylprednisolone. The patient's white blood cell count recovered the next day, and he was discharged after 2 days of hospitalization.
Conclusion: We diagnosed the patient with contrast media-induced transient leukopenia, which is a rare phenomenon.
Keywords: Allergy; ER; computed tomography; contrast media; drug‐induced leukopenia.