Liz Buchanan BVSc MRCVS
I would be tempted to continue giving the Panacur unless told otherwise by your vet, but report the diarrhoea to them so that they can make this decision if necessary. At some point, they may want to check to ensure that fluid loss through the poo is too much. Most diarrhoea is self-limiting and will resolve in a few days; vets sometimes will reccommend a plain, bland diet in the meantime. They will, however, be on the lookout for dehydration or other matters that need their attention.