"If it's reversed naturally without medication and it's followed by three or four nights of complete insomnia, then it's a bipolar variant," said Dr. Rosalind Cartwright, professor emeritus at Rush University Medical Center and author of "The Twenty-Four Hour Mind." "Then, it's treated as if a mood stabilizer is needed. It tends to respond to lithium or depakote."
The only way to really address the symptoms of Kleine-Levin Syndrome is to adapt to it. There are usually signs that an episode is coming.
"They tend to become less active and want to sleep more, and they're kind of confused and in a cloud," said Schoumacher.
While experts don't think sufferers are in any danger during their sleep episodes, they probably shouldn't be alone.
"The're cognitively impaired, they have an increased appetite and decreased inhibitions," said Silber.
Lori Haller always makes sure someone is with Eric during his periods of sleep.
"He'll only want fast food, and someone has to go get his food, and he's basically bedridden," she said.
As disabling as it is to Eric, who had to miss a lot of school, his condition is also debilitating for Lori.
"I feel like a part of me dies with him. I lose him for that amount of time, because he's not the same kid."
If she dresses carefully and positions herself properly, Carla Sosenko, 32 from Brooklyn, N.Y., knows no one will be able to see any of the physical flaws that she works hard to conceal.
But, unlike the bumps and bulges that many people would like to hide, Sosenko's are the result of a rare congenital disorder called Klippel-Trenaunay Syndrome (KTS).
"It was always about my appearance, which is, in a lot of ways, fortunate," Sosenko said. "In terms of the medical issues, I never felt like I had them."
Symptoms can vary widely and, depending on the severity of the condition, can include pain, blood clots, seizures, blindness and mental retardation. Excessive bone growth can lead to amputation of the enlarged limb.
Because KTS falls between specialties -- vascular, orthopedic and lymphatic -- the disorder was often misdiagnosed and treated inappropriately.
"There is tremendous confusion [about KTS]," said Dr. John Mulliken, co-director of Vascular Anomalies Center at Children's Hospital Boston. "These patients used to be medical nomads. No one doctor can take care of these patients."
Sosenko's right leg is slightly larger than her left, her back is uneven with fat deposits, and a plum-colored mark from enlarged blood vessels under the skin, called a port-wine stain, stretches from her torso to her right thigh.
Sosenko said that many people she meets might not notice her lumpy back or that she drags her right leg slightly when she walks. Others might notice and not comment and still others might ask her about it.
"If a perfect stranger says something cruel, it hurts," Sosenko said. "That will hurt no matter how much progress I make, no matter how confident I feel."
Still, Sosenko admitted that the varicose veins that she has can hurt and excessive walking can be taxing because of the length difference between her legs.
Fortunately, Sosenko's condition is not painful nor has it prevented her from any of her favorite activities, such as yoga.
"It's discomfort, it's not debiblitating," Sosenko said.
Christopher Sands, 25, has been battling hiccups, normally a mundane, short-lived biological function, for more than two years.