(NEW YORK) -- It was blinding headaches that sent the 46-year-old New Yorker running to her doctor.
Alarmed, her physician did blood work and ordered an expensive MRI of the brain, as well as another kind of brain scan. Everything checked out as normal. There was no apparent explanation for the sudden pounding in the patient's head, a pounding that was not eased by medications.
Stumped, the doctor sent her to a neurologist, Dr. Orly Avitzur of Terrytown, N.Y., who finally unraveled the mystery.
"When I went to examine her and simply touched her scalp, she pulled away and winced when my fingertips touched her quite gently," Avitzur said, describing the unnamed patient, a social worker.
Avitzur took a closer look and noticed something unusual. "She had hundreds of these tightly braided hair braids," she said.
It turns out the woman was suffering not from a neurological condition, but from a side effect of her new hair extensions. She'd gotten the popular beauty treatment a few weeks earlier, right at the time the headaches began.
"It was pretty clear to me that she did not need a work-up," Avitzur said, "but that she needed to remove her extensions."
Avitzur, who is also the medical adviser for Consumer Reports, has now written an article warning about the dangers of hair extensions, which go beyond headaches. Avitzur warns about permanent hair damage, and even a kind of baldness called traction alopecia, caused by the pulling and weight of the extensions.
"I think the risk of baldness, if you start to get hair loss, that's really my bottom line," Avitzur said, "then stop immediately." Hair extensions first became popular with actresses and other celebrities, some of whom are now reportedly suffering from their own hair loss as a result of the extensions. The procedure, which can add fullness and length to a head of hair, is now solidly mainstream.
"Very popular, huge," longtime Chicago cosmetologist Grace Santiler-Nowik said, adding that the extra tresses are safe if put-in and cared for correctly.
"It's not something you tread into lightly," she told ABC News. "People want their hair thick and long, but they forget there's a whole upkeep portion of it they have to maintain."
It's important to make sure the stylist has experience with the kind of hair extensions you're using, and with the method they're using to attach the extensions. If they're attached too tightly, or weigh too much, problems can develop, according to Santiler-Nowik, who is president of the Professional Beauty Association's Professional Council.
Santiler-Nowik also warns that customers have to return to the salon at regular intervals to have the extensions removed and replaced, and need to take a break from the hair pieces if they're causing damage to a person's hair.
"I think it's important for people to get education, there's always a safe way to do things and a smart way to do things," she said.
It was a beauty pageant that led 26-year-old Amanda Jones to try hair extensions. She used them for two Miss Virginia competitions.
Jones, who finished in the top five both times, had wildly different experiences. The first time around, she had the extensions glued to her own hair, and said there were no problems. Last year, she tried a different method; the extensions were sewn onto her own hair.
"That was the most painful experience of my life," Jones said. "I had them in for maybe three weeks. My scalp was red and bleeding. I lost a lot of hair."
Jones said as soon as the pageant was over, she took off the $500 extensions. "They were so tight, they were physically pulling my hair out," she said.
Jennifer Meram says she has avoided that problem by using clip-on extensions, which she finds easy to put in and take out. The 22-year-old from San Diego, who has been using hair extensions for about four years, is a true believer.
"I just think that every girl feels prettier with pretty hair," she said. "If I feel like if I'm having a bad hair day, I simply put on my extensions.
"To me, it makes a difference. It's like an instant confidence level."
Others see the beauty treatment as an option that discourages people from taking care of their own hair.
A'Lelia Bundles, a great-great-granddaughter of Madam C.J. Walker, who started a successful line of beauty and hair products for black women in the early 1900s, bemoans the fact that hair extensions are widely used in the black community.
"Part of the reason Madam Walker started her hair care company a hundred years ago was because women were going bald because of braiding their hair very tightly and over-processing their hair," she said. "It is as if we have not learned anything in a century."
But the allure of a full head of long hair has wide appeal. Despite her painful experience, former pageant contender Jones says, "I would probably use them again at some point, but I would try a different method this time."
As for Dr. Avitzur's patient who had the excruciating headaches, she says the woman, who had spent many hours and lots of money on the extensions, refused to believe they were the cause of her problem.
"A lot of us do crazy things for the sake of appearance," Avitzur said.
Copyright 2013 ABC News Radio