The literature discussed in depth the temporal relationship between different antiparkinsonian drugs and dyskinesias [7,21,22,23,24,28,39,40,41,42,43,44,45], highlighting the major role played by levodopa over dopamine agonists [22,23,24,25,26,27], COMT inhibitors [28] and MAO inhibitors [29]. Here, COMT is linked to drug-induced dyskinesia.