Whenever you think you have them beat, they always come back!

Why is it so difficult to get rid of fleas?

I am grateful that I have a white dog. It's easy to spot those pesky fleas against Zoe's white fur, but I still wage a never-ending battle of pulling them out and dunking them in a cup of soapy water to drown them. Sometimes it takes hours to do this. Now I know what a monkey feels like during a grooming session.

Fellow dog owner Gary Tom suggests a few strategies in flea-killing. "Constant vacuuming of the house helps," he says. "Make full use of your metal flea comb by crushing the fleas against the comb teeth with your fingernail. It makes a satisfying 'pop' when you crush them. Apply your topical medicine (Advantage or Frontline) every three weeks if it's really a problem.

"When it's bad, use a flea-killing shampoo," says Tom.

I also used topical treatments that are absorbed through the skin. The fleas would be stopped for several months, then they eventually would win the war and start infesting Zoe again.

Sergeant's Flea & Tick shampoo used to work, but not anymore. The green liquid was always used on our pets while I was growing up and was always a winner. I bet the manufacturer changed the formula to a less effective one.

Zoe would scratch and bite incessantly, all day and all night, waking me up. The poor dog was tortured — and that's saying it mildly — by these biological terrorists.

Dr. Scott Harada of The Pet Clinic says, "Controlling fleas takes an understanding of the life cycle of the flea, your pet's lifestyle and environmental factors such as stray cats and dogs walking past your house."

A friend recommended Comfortis, a new chewable tablet that works internally for a month. I called Dr. Harada the next day asking for it. Six pills cost $90! I couldn't believe how expensive it was.

Although Dr. Harada hasn't seen any serious reactions toward Comfortis, there can be. He advises every pet owner to consult their veterinarian on the best type of treatment for their pet.

The box says it kills fleas in the first 30 minutes. I admit I was skeptical that anything could work that fast and effectively against these demons from hell.

Zoe ate her first Comfortis pill a week ago. I couldn't believe my eyes! The fleas were literally dropping off her, dying. I pulled those black creatures off her fur and from her blanket, cursing each one for making her so uncomfortable.

For now, Zoe is flea-free and has stopped scratching. There's finally peace in the house for her and me.