I am sorry to hear that your kitties are very itchy and you are unsuccessfully battling fleas.
First realize that only 5% of the flea population lives on your cat, the rest is in the environment.
You need to vacuum your home throughly to remove as many eggs and larvae as possible. Concentrate on cracks and crevices, along baseboards, under furniture and areas where they like to sleep and eggs and larvae are at their highest numbers. Vacuum daily and throw away the bag.
You also need to use effective products on your cats. I recommend either Frontline Plus or Advantage ll as they are effective and safe products. Another option is the new Seresto Flea collar. I don't normally recommend flea collars, but this one really works and lasts for at least 6-8 months.If you have other pets all animals must be treated or they will serve as flea reservoirs.
I also recommend treating the home environment with a product that has an adulticide (kills adult fleas) as well as an insect growth regulator to stop egg and larvae from developing. A great product is Siphotrol II Plus Premise spray. I like it because it has an insect growth regulator as well as an adulticide. You can spray it under furniture and into cracks crevices and along baseboards where fleas and their offspring hide. It should be used every 2 weeks and no vacuuming for 2 to 3 days after using it to allow it to settle in. Here is a link to show you the product: http://www.amazon.com/Siphotrol-Plus-Premise-Spray-16oz/dp/B000RGKX7M
The trouble with foggers is that they don't go under furniture or penetrate cracks and crevices so they just aren't effective where they need to be. And they end up in the air where they are nasal irritants for animals and people alike.
Your other option is to have a professional exterminator treat your home and outdoors since Kiki goes outside. Ask for a guarantee and make sure that the products they use don't contain organophosphates and do have an adulticide and an insect growth regulator.
The key with flea treatment is consistency, not stopping too quickly, and using effective products.
To control allergic symptoms you can try:
1) Benadryl (diphenhydramine only, the combination products with decongestants and acetaminophen are toxic to cats) at a dose of 1mg to 2mg per pound of body weight every 8 hours. That's a half of 25mg tablet every 8 hours for a cat that is 8 to 15 pounds. Benadryl is very bitter and some cats will drool excessively or may even vomit because of that. That doesn't mean it is making your kitty ill, they just hate the taste. If that's the case try a different antihistamine.
2) Chlorpheniramine at 4mg twice daily.
3) Zyrtec (Cetirizine hydrochloride) at a dose of 5 mg per cat given orally every 24 hours. Make sure it is NOT the formulation with a decongestant (such as Zyrtec-D) because cats cannot tolerate decongestants.
Combined with high doses of omega-3 fatty acids antihistamines work to relieve her itchiness. I like 3V caps or Derm Caps as they are reputable, high quality products. I recommend a dose based upon the EPA portion (eicosapentanoic acid) of the supplement as if we do that the rest of the supplement will be properly balanced. Give her/him 20mg of EPA per pound of body weight per day. For example an 8 pound cat could take 160mg of EPA per day. Antihistamines and omega-3 fatty acids work synergistically, better together than either one alone. These should help reduce the itch. Be aware that antihistamines can cause drowsiness or hyperactivity which should resolve with continued use.
Best of luck with your flea troubles.