I understand that you are wondering what type of flea medication is safe to use on your nursing queen, Ivy and her kittens.
You can safely apply Frontline Plus to mom when she is still nursing her kittens.
I would wait until the kittens have just nursed, then apply the Frontline Plus flea control as directed and keep her away for a few hours to let it dry, just to be safe, but it should not affect the kittens at all.
Frontline Plus can be used on the kittens too once they are 8 weeks or older.
I would make sure the kittens have a good meal and then separate mom and apply the product, as mom needs to be separated from the kittens for a few hours after application.
Do not use the over counter preparations. Many of those use the older insecticides which can be toxic, especially to kittens.
Young (neonatal) kittens should not have any flea medications applied. A thorough flea combing to remove any stray fleas is best.
Make sure to wash the bedding in their nesting box in steaming hot water daily to kill the flea larvae, and eggs before they have a chance to mature.
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