Lauren Johnson, 12, from Virginia has baffled doctors because she sneezes over 12,000 times in a day.
"I can't stop sneezing. It goes off about eight to nine times a minute," Fox News quoted Lauren, as saying.
The syndrome known as "machine gun sneezing," started nearly two weeks ago when Lauren caught a cold.
Her mum, Lynn Johnson said: "I know this is terrible for her."
The sixth-grader has had to stay away from school because of her condition and has seen six doctors since the sneezing began.
A neurologist said Lauren's condition may be "irretractable psychogenic disorder," which could have been caused due to stress, according to the report.
Lynn said: "There's less than 40 cases ever documented in the entire world...Nobody really knows how to treat it, what's going to work, and even in the cases where it might have worked or turned the sneezing off for awhile, a lot of times it comes back again and then you're right back to where you started."
She added: "It turns off when she sleeps...Only in a deep REM sleep it turns off."