Provided are an agent for the treatment and/or prophylaxis of a movement disorder, the agent for the treatment and/or prophylaxis wherein the movement disorder is extrapyramidal syndrome, the agent for the treatment and/or prophylaxis wherein the movement disorder is bradykinesia, gait disturbance, dystonia, dyskinesia or tardive dyskinesia, the agent for the treatment and/or prophylaxis wherein the movement disorder is a side effect of L-DOPA and/or dopamine agonist therapy, and the like, each containing a thiazole derivative represented by the formula (I) wherein R1 represents aryl and the like, and R2 represents pyridyl or the like, or a pharmaceutically acceptable salt thereof as an active ingredient.
