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How to protect your cat or kitten from parasites
Apply topical insecticides.
Use an effective, veterinarian recommended product that is appropriate for the age of your kitten. Be aware that different spot on products contain different active ingredients, not all of which are effective or safe.
Apply the product to the back of the cat's neck where they can't reach it to rub off. This is usually a good method for any cat, but if it proves ineffective or the cat manages to get it off, then you should consider using another product--the flea collar method, spray, or shampoo.