In contrast with previous studies (Cordeiro et al., 2018; Graziola et al., 2019), only a small proportion of patients had dyskinesia (5.3%) and no patient was identified carrying the PRRT2 mutation which is a well-known, most-common cause of the paroxysmal dyskinesia (Erro et al., 2014; De Gusmao and Silveira-Moriyama, 2019). This evidence concerns the gene PRRT2 and drug-induced dyskinesia.