A pharmaceutical composition for use in treating a subject suffering from itch or pruritus, said composition comprising an effective amount of at least one compound having the formula: Ar-B-Ar' wherein: -B- represents: -X-Y-Z-, wherein: X represents -(CH 2) n (wherein n is 0-6); Y represents oxygen, sulphur, >NH or is absent; Z represents >C=O >O or >COO or is absent; and wherein at least one of X, Y and Z must be present; Ar represents an indole nucleus ring system: Ar' represents an alpha-, beta- or gamma-pyrone nucleus ring system: wherein each of R 1-4 substitutes the ring system Ar at any available position (including the N-position) and each of R 1' -R 2' substitutes the ring system Ar' at any available position and wherein each of R 1-4 and R 1'-2' independently represents hydrogen, oxygen, halo, halo-C 1-5 alkyl, aryl, acyl, a C 5-7 heterocyclic group containing 1-3 hetero atoms independently selected from nitrogen, oxygen or sulphur; a C 6-8 heteroaryl group containing 1-3 hetero atoms independently selected from nitrogen, oxygen or sulphur, C 1-5 alkyl, C 2-5 alkenyl, C 2-5 alkynyl, aryl- C 1-5 alkyl, aryl- C 2-5 alkenyl, aryl-C 2-5 alkynyl, hydroxy-C 1-5 alkyl, nitro, amino, cyano, cyanamide, guanidino, amidino, acylamido, C 1-5 alkylamine, C 1-5 alkylamido, hydroxy, thiol, acyloxy, azido, C 1-5 alkoxy, carboxy, carbonylamido or styryl; wherein said arylalkyl, arylalkenyl, aralalkynyl, or styryl group optionally can be ring-substituted by one to four substituents independently selected from the group consisting of hydrogen, halo, halo-C 1-5 alkyl, aryl, a C 5-7 heterocyclic group containing 1-3 hetero atoms independently selected from nitrogen, oxygen and sulphur; a heteroaryl group containing 1-3 hetero atoms independently selected from nitrogen, oxygen and sulphur; C 1-5 alkyl, C 2-5 alkenyl, C 2-5 alkynyl, aryl-C- 1-5 alkyl, aryl-C 2-5 alkenyl, aryl-C 2-5 alkynyl, hydroxy-C 1-5 alkyl, nitro, amino, cyano, cyanamido, guanidino, amidino, acylamido, hydroxy, thiol, acyloxy, azido, alkoxy, carboxy, carbonylamido, S-alkyl or alkylthiol; and either of R 3 or R 4 further can include or represent a bond to B; wherein Ar is bonded to B at position 3 on the five-membered ring portion of the Ar ring and Ar' can be bonded to B at any carbon on the Ar' ring not substituted by R 1' and R 2'; or a salt, stereoisomer, or racemic mixture thereof, and at least one pharmaceutically acceptable diluent, preservative, antioxidant, solubilizer, emulsifier, gelling agent, adjuvant or carrier. X represents -(CH 2) n (wherein n is 0-6); Y represents oxygen, sulphur, >NH or is absent; Z represents >C=O >O or >COO or is absent; and wherein at least one of X, Y and Z must be present; Ar represents an indole nucleus ring system: Ar' represents an alpha-, beta- or gamma-pyrone nucleus ring system: wherein each of R 1-4 substitutes the ring system Ar at any available position (including the N-position) and each of R 1' -R 2' substitutes the ring system Ar' at any available position and wherein each of R 1-4 and R 1'-2' independently represents hydrogen, oxygen, halo, halo-C 1-5 alkyl, aryl, acyl, a C 5-7 heterocyclic group containing 1-3 hetero atoms independently selected from nitrogen, oxygen or sulphur; a C 6-8 heteroaryl group containing 1-3 hetero atoms independently selected from nitrogen, oxygen or sulphur, C 1-5 alkyl, C 2-5 alkenyl, C 2-5 alkynyl, aryl- C 1-5 alkyl, aryl- C 2-5 alkenyl, aryl-C 2-5 alkynyl, hydroxy-C 1-5 alkyl, nitro, amino, cyano, cyanamide, guanidino, amidino, acylamido, C 1-5 alkylamine, C 1-5 alkylamido, hydroxy, thiol, acyloxy, azido, C 1-5 alkoxy, carboxy, carbonylamido or styryl; wherein said arylalkyl, arylalkenyl, aralalkynyl, or styryl group optionally can be ring-substituted by one to four substituents independently selected from the group consisting of hydrogen, halo, halo-C 1-5 alkyl, aryl, a C 5-7 heterocyclic group containing 1-3 hetero atoms independently selected from nitrogen, oxygen and sulphur; a heteroaryl group containing 1-3 hetero atoms independently selected from nitrogen, oxygen and sulphur; C 1-5 alkyl, C 2-5 alkenyl, C 2-5 alkynyl, aryl-C- 1-5 alkyl, aryl-C 2-5 alkenyl, aryl-C 2-5 alkynyl, hydroxy-C 1-5 alkyl, nitro, amino, cyano, cyanamido, guanidino, amidino, acylamido, hydroxy, thiol, acyloxy, azido, alkoxy, carboxy, carbonylamido, S-alkyl or alkylthiol; and either of R 3 or R 4 further can include or represent a bond to B; wherein Ar is bonded to B at position 3 on the five-membered ring portion of the Ar ring and Ar' can be bonded to B at any carbon on the Ar' ring not substituted by R 1' and R 2'; or a salt, stereoisomer, or racemic mixture thereof, and