
Hi taken from their website
Special Precautions and Warnings
Studies with milbemycin oxime indicate that the margin of safety in certain dogs of Collie or related breeds is less than in other breeds. In these dogs, the recommended dose should be strictly observed.
The tolerance of MILBEMAX in young puppies from these breeds has not been investigated.
During treatment with MILBEMAX, no other macrocyclic lactones should be administered.
web site
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