It is intended to provide a novel quinazoline derivative with less skin irritation and an excellent action of strongly suppressing scratching behavior and a pharmaceutical composition containing the quinazoline derivative as an active ingredient. The present invention is directed to the quinazoline derivative represented by the general formula [1] or a pharmaceutically acceptable salt thereof. In the general formula [1], R 1 represents hydrogen or the like, R 2 represents hydrogen or the like, R 3 and R 4 are the same or different and represent hydrogen, alkyl, alkoxy or halogen, R 5 is combined with R 6 to represent alkylene or represents hydrogen, hydroxy, alkyl, phenyl or alkoxy, R 6 represents (1) alkyl, (2) cycloalkyl, (3) phenyl, (4) a 5- to 10-membered aromatic heterocyclic group containing one to three heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom, or (5) -N(R 61 ) (R 62 ).
