Baking soda can be applied to dogs and cats can in order to kill fleas, but it is not our first recommendation that you do so.
Baking soda acts as an agent to dehydrate fleas and flea larva and kills them in that manner. It is more often spread in carpeting and floors for this purpose.
When spread directly on the animal skin, it does kill fleas, but in a slow and less effective manner than other products, and it also has the added disadvantage of being ingested by the cat or dog when he licks his body.
You’re better suited giving your pet a flea bath with flea shampoo to kill the fleas on his body, and also administering a once month medication like Advantage to really get the flea infestation under control.