This invention concerns the compounds of formula the N-oxide forms, the pharmaceutically acceptable addition salts and the stereochemically isomeric forms thereof, wherein n is 0, 1 or 2; m is 1 or 2, provided that if m is 2, then n is 1; ═Q is ═O or ═NR3; X is a covalent bond or —O—, —S—, —NR3—; R1 is Ar1, Ar1C1-6alkyl or di(Ar1)C1-6alkyl, wherein each C1-6alkyl group is optionally substituted; R2 is Ar2, Ar2C1-6alkyl, Het or HetC1-6alkyl; R3 is hydrogen or C1-6alkyl; L is a piperidine derivative of formula (a-1) or a spiro piperidine derivative of formula (a-2); Ar1 is phenyl or substituted phenyl; Ar2 is naphtalenyl; phenyl or substituted phenyl; and Het is a monocyclic or bicyclic heterocycle; each monocyclic and bicyclic heterocycle may optionally be substituted on a carbon atom; as substance P antagonists; their preparation, compositions containing them and their use as a medicine.