IL13 and Timothy syndrome: It has been shown that TNF-α and IL-13 concentration were increased in the children receiving antipsychotics when the tic symptoms exacerbated, while serum IL-4 concentration was increased in children receiving antipsychotics when the symptoms relieved (24), but another study showed that serum TNF-a concentration did not show any differences between medicated and non-medicated TS patients (25).