You should probably have your veterinarian refer you to a veterinary dermatologist who can assist you in attempting to alleviate the severe reaction your pet experiences to fleas. The bedding should then be washed in hot soapy water to kill the remaining flea larvae. There are two types of pills for flea control. The newest product, Program, contains the growth-regulator lufenuron. This product does not kill fleas, but it prevents them from reproducing.
Program is safe for the pet and is convenient, as the pill is given only once a month.
Proban is the brandname of the product containing the organophosphate insecticide cythioate. When given orally to a dog, it causes the animal's blood to be lethal to fleas that consume it. After sucking the blood, the flea will die, but it has already injected its salivary secretions, so a flea-allergic animal will react anyway. This is a prescription medication, available only through your veterinarian. It is not registered for cats.