The present invention relates to diazepine derivatives of formula (I) wherein R represents hydrogen or C.sub.1-4 alkyl; R.sub.1 represents hydrogen or C.sub.1-4 alkyl; R.sub.2 represents trifluoromethyl, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, trifluoromethoxy or halogen; R.sub.3 represents halogen or C.sub.1-4 alkyl; R.sub.4 represents hydrogen, halogen, C.sub.1-4 alkyl or COR.sub.6; R.sub.5 represents hydrogen, C.sub.1-4 alkyl or R.sub.5 together within the R.sub.1 represents C.sub.3-7 cycloalkyl; R.sub.6 represents hydroxy, amino, methylamino, dimethylamino, 5 membered heteroaryl group containing 1 to 3 heteroatoms selected independently from oxygen, sulphur and nitrogen or a 6 membered heteroaryl group containing 1 to 3 nitrogen atoms; m or n are independently zero or an integer from 1 to 3; X and Y are independently NR.sub.7 or methylene; provided that when X is NR.sub.7, Y is methylene and when X is methylene, Y is NR.sub.7; R.sub.7 represents hydrogen, C.sub.1-4 alkyl or C.sub.3-7 cycloalkyl; and pharmaceutically acceptable salts and solvates thereof; to process for their preparation and their use in the treatment of condition mediated by tachykinins