Puppies under six weeks of age are vulnerable to chemicals, so bathing puppies in mild dish detergent is the preferred method of flea control in most cases. The Daily Puppy suggests checking and combing puppies daily until the puppy is old enough to bathe in a flea shampoo.
Puppies do not have high blood volume, states The Daily Puppy, making very young puppies vulnerable to anemia. Puppies should be examined and taken to the vet immediately if their gums are pale or white because anemia can be fatal, The Daily Puppy adds.
Bathing puppies in mild dish detergent and lukewarm water will kill most fleas, but they also recommend using a flea comb to remove any surviving pests. Bedding should also be thoroughly washed.