Patent ID: 8450357

Claim:
A composition for the treatment of a parasitic infestation in an animal comprising at least one 1-arylpyrazole compound of formula (IB): wherein: R 1b is alkyl, CN or halogen; R 2b is S(O) n R 14b or 4,5-dicyanoimidazol-2-yl or haloalkyl; R 14b is alkyl or haloalkyl; R 3b is a hydrogen, halogen, —NR 7b R 8b , —S(O) m R 9b , —C(O)R 9b , —C(O)OR 9b , alkyl, haloalkyl, —OR 10b or an —N═C(R 11b )(R 12b ); R 6b is a halogen, haloalkyl, haloalkoxy, S(O) q CF 3 or SF 5 group; R 7B and R 8B independently represent a hydrogen, alkyl, haloalkyl, —C(O)alkyl, —S(O) r CF 3 , acyl or alkoxycarbonyl; or R 7b and R 8b can together form a divalent alkylene radical which is optionally interrupted by one or two divalent heteroatoms; R 9b is an alkyl or haloalkyl; R 10b is hydrogen, alkyl or haloalkyl; R 11b is hydrogen or alkyl radical; R 12b is an optionally substituted aryl or an optionally substituted heteroaryl group; R 4b and R 13b represent, independently of one another, hydrogen, halogen CN or NO 2 ; m, n, q and r represent, independently of one another, an integer equal to 0, 1 or 2; and Z represents a trivalent nitrogen atom or a C-R 13b radical, the three other valencies of the carbon atom forming part of the aromatic ring, in a first veterinarily acceptable carrier; at least one formamidine compound of formula (II): wherein: x is an integer from 0-5; R 14 is alkyl, halogen or —OC(═O)NR a R b , wherein R a and R b are independently hydrogen or alkyl; R 15 is hydrogen or alkyl; R 16 is hydrogen or alkyl; and R 17 is hydrogen, alkyl or in a second veterinarily acceptable carrier; and optionally at least one crystallization inhibitor, wherein the 1-arylpyrazole compound(s) and first veterinarily acceptable carrier are compartmentalized together, and not in fluid communication with, the formamidine compound(s) and the second veterinarily acceptable carrier.