When he was in high school, Eric Haller was a first-string center on the football team and also played on the basketball team.
Despite his love of sports, he had to quit both.
Because of that condition, he missed too many basketball practices and football games.
"He missed a lot of things in his life," said Lori Haller, his mother. "He missed his prom and school dances."
Eric is now 20, and is still missing important events of his adulthood.
"He missed President Obama's election," Lori said. "We have to fill him in on a lot of things he misses."
Eric Haller is just one of many Americans who experience some form of rare medical disorder. Sometimes these disorders fall between many medical specialties, and they often involve some sort of normal bodily function that occuring in some sort of extreme way .
For some there are cures and treatments. Usually, however, people with these strange conditions must move forward with their lives, coping with physical, social and emotional discomfort, because there is no cure.
The following pages feature some of the more unusual medical conditions that have received recent media attention.
Kleine-Levin Syndrome generally strikes adolescents. People who have it experience episodes of extreme sleepiness that could last from days to weeks. During those episodes, sufferers will sleep sometimes 20 hours a day, and will wake up only to eat or go to the bathroom. The length of time between episodes can vary from a couple of weeks to several months. In between the periods of excessive sleep, people who have the condition are very normal.
It's also characterized by bizarre behavior during these episodes.
"When they wake, they really want to eat a lot and they're not normal," said Dr. Robert Schoumacher, professor of pediatrics at the University of Tennessee Health Science Center.
"About half of them develop feelings of hypersexuality and display inappropriate sexual language and behavior," said Dr. Michael Silber, professor of neurology at the Mayo Clinic's Center for Sleep Medicine.
Lori Haller said her son is barely recognizable during his sleep episodes.
"He looks different, acts different, he's irritable and looks as if he's in a nightmare state," she said.
He's now approaching the age when experts say Kleine-Levin Syndrome seems to just go away on its own.
"It starts to get better in the late 20's," said Silber. "Most cases resolve spontaneously 10 or more years after the first onset," he added.
There's no known cause and no cure for Kleine-Levin Syndrome, and sleep specialists say there aren't any drugs that work particularly well to treat the symptoms, although they say some patients respond to valium or lithium.
There is another form of Kleine-Levin Syndrome that does respond better to medication.