AbstractAim. Seizures can produce systemic changes, including elevated body temperature, white blood cell count, and C‐reactive protein levels, which raises concern for potential infection. We describe seizure‐induced inflammation‐like responses and discuss how these changes may be distinguished from those associated with infection.Methods. We prospectively investigated 140 consecutive visits to the emergency room, in which patients presented with seizures. We defined elevated body temperature, white blood cell count, or C‐reactive protein levels as inflammation‐like responses. We investigated the occurrence of inflammation‐like responses, characteristics of the seizures, neurological status at the initial visit, outcomes, and clinical findings to determine the presence of infection. We ascertained whether the patients had infection or not based on the overall information post‐discharge.Results. An inflammation‐like response was observed in 56.3% of all visits and 19.3% were diagnosed with concurrent infection. Among the visits with inflammation‐like response, 34.7% were shown to have an infection. Increases in body temperature and C‐reactive protein levels were milder (<39°C and <6 mg/dl, respectively) in patients without infection compared to those with infection, whereas there was no difference in leukocytosis, with regard to the presence or absence of infection. Increased body temperature occurred only in cases of generalized tonic‐clonic seizures, whereas leukocytosis and elevated C‐reactive protein levels were reported in patients with any type of seizure. Body temperatures returned to normal within eight hours in uncomplicated cases.Conclusion. Seizures frequently induce an increase in body temperature, white blood cell count, or C‐reactive protein levels, making it challenging to distinguish these changes from those associated with infection. Nonetheless, elevated body temperature in the absence of generalized tonic‐clonic seizures, above 39°C, or persisting for more than eight hours after recovery of consciousness, and C‐reactive protein levels above 6 mg/dl warrant close observation and consideration for concurrent infection.