ABSTRACT.The cerebrospinal fluid (CSF) concentration of the inhibitory neurotransmitter gamma‐aminobutyric acid (GABA) was analysed in 41 children with febrile convulsions (FC), 41 febrile controls of similar age (control group 1), and 59 controls, who had no fever and/or were outside the age range for FC (control group 2). A significant correlation between CSF‐GABA and age was demonstrated for controls (1 + 2) (r= 0.63, p<0.00001), as well as for patients with FC (r= 0.42, p= 0.003). Patients with FC did not differ significantly from control group 1 in respect to CSF‐GABA. Duration of FC was related to both CSF‐GABA and age (GABA: r=−0.29, p<0.05; age: r =−0.32, p1 year of age, a significant negative correlation between CFC‐GABA and body temperature was found (r=−0.34, p = 0.01). The low CSF‐GABA in the FC‐labile age group, the negative correlation of CSF‐GABA to body temperature, and the negative correlation of the duration of FC to both CSF‐GABA and age, all indicate that GABA could be of importance in th