ST. CLAIR SHORES, Mich. -- St Clair Shores police said a woman is lucky to be alive after her American Bulldog attacked and cornered her inside a bathroom until officers arrived.

Officer Gerald Sems and Animal Control Officer Tom Massey shot the animal with a Taser gun to enter the home to give the woman medical treatment.

The woman, who was badly bitten by the dog, called police from the bathroom using a cell phone.

"How big is your dog?" the dispatcher asked during the call.

"He's big! He comes up to my waist," the woman said during the call. "He's about 110 pounds."

According to a transcript of the 911 call, the dispatcher asked, "Ok, where are you bit at?"

"On my arm," the caller answered.

Dispatcher: "Do you have a clean cloth to put over it to stop the bleeding?"

Caller: "Yes!"

Dispatcher: "Ok. We'll have somebody on the way."

Police said the dog is now at the Macomb County Animal Shelter, where it's being quarantined and observed to see if it has rabies.

The woman is being treated at Mount Clemens Regional Medical Center.

The dog belonged to the woman and her boyfriend.

The woman said they got the dog from a Plymouth man who had offered it for free on Craigslist.

The woman said she was lying on the coach when the dog starting barking at some landscapers at the neighbor's. She told the dog to be quiet, but it lunged at her and started biting her.

Authorities said the dog may be euthanized.