If your dog has fleas, so does your house. If you only treat your dog, the fleas will move on to another warm body for their bloodsucking -- you. To get rid of an infestation completely, you need to treat your house for fleas too, as well as your yard (where the fleas originated).
To treat your house, vacuum thoroughly, including the furniture, and throw away the vacuum bags when you're finished. Wash all rugs and bedding. Next, apply a product to treat the house. One natural option is a boric acid-based powder. You sprinkle it on your carpet, brush it into the carpet fibers using a broom, then vacuum. The residue will remain in the carpet and kill flea larvae, but it's not toxic enough to harm you or your dog.
There are lots of insecticides available to kill fleas in your home, such as sprays, liquids and flea bombs, or foggers. While these products can be effective, they're also highly toxic. If you choose to avail yourself of these products, make sure to follow the directions carefully. Keep pets and children away from the house while you're treating it, and wait until the product has dried or dispersed to bring them back in.
You can also build a flea trap. Flea traps alone won't rid your house of fleas, but they can help determine how many adult fleas are still hanging around. Hang a light source over a sticky, disposable surface (flypaper works well) or a bowl of soapy water. The heat from the light source attracts any nearby fleas, many of which will then get caught. You'll notice the fleas as small, dark, flat-bodied insects, roughly the size of a comma.
Next, treat your yard. Outdoor flea-control products kill adult fleas and contain insect-growth regulators to catch immature fleas before they can mature. Moist, shady areas are favorite flea playgrounds and breeding grounds, so clear out fallen leaves, pine needles, wood and debris from under trees and bushes. Treating your whole yard is ideal, but concentrate on areas your dog frequents, such as along the fence line and around his doghouse. Professional pest-control companies can also handle fleas, but you'll want to make sure that the chemicals they use are safe for your dog. There's a natural, safe option here, too: spraying your yard with nematodes. These little worms won't harm anything but fleas and garden parasites like grubs.
As long as you treat your pet, home and yard, your dog's flea infestation will soon be nothing but a bad memory.