Matthew Horsnell began falling asleep for no reason when he was in sixth grade.
“I would go to bed at 8:30 at night, yet every morning I would wake up and struggle to get out of bed,” said Horsnell, now 43. “I would fall asleep on the couch while I was waiting for my mom to take my brother and I to school and nod off again during the 20-minute ride. Then throughout the day, I might move to the back of the class to catch another few winks.”
By age 20, Horsnell began losing control of his body for brief periods when he felt a strong emotion, falling or slumping to the ground conscious but paralyzed — a condition called cataplexy.
“If I’m startled or someone tells a really funny joke, my knees may buckle, or I may drop something. I can even fall over,” he said. “What’s scary and embarrassing is that I can see people come to help me, but I’m unable to respond.”
Horsnell has narcolepsy, a sleep disorder that makes it hard to stay awake for long periods. Not only will a person fall asleep repeatedly during the day, but they will have extremely disrupted sleep at night, said Jennifer Mundt, assistant professor of sleep medicine, psychiatry and behavioral sciences at Northwestern University’s Feinberg School of Medicine in Chicago.
Narcolepsy is estimated to affect one in 2,000 people in the United States and some 3 million worldwide, according to the Narcolepsy Network, a non-profit patient advocacy group. However, that estimate is likely low due to difficulties with obtaining a proper diagnosis, said Mundt, who treats patients with narcolepsy and conducts research on the condition.
In fact, it’s estimated that only 25% of people who have narcolepsy are diagnosed and receive treatment, according to the Narcolepsy Network.
“On average, it takes 10 or more years to get diagnosed, so we know there’s a lot of people out there who may have it and are going untreated,” Mundt said. “Many people are never seen by a sleep specialist, who is one of the few physicians trained to recognize the symptoms.”
A large percentage of people with narcolepsy have cataplexy as well, which along with excessive sleepiness disrupts a person’s ability to socialize, work at a job, drive a car or even have close relationships that trigger intense emotions, Mundt said.
“There’s been so much stigma around narcolepsy,” she said. “In movies it’s usually depicted as this very comical thing, like it’s a joke. It’s not a joke, it’s a very serious illness.”
‘Please don’t call an ambulance!’
In his early years at college, Horsnell was doing a squat routine with particularly strenuous weights at a local gym when he felt his knees begin to wobble. Suddenly, he was afraid.
“Fear overwhelmed my body, and so when I went down for that next rep, my body just gave out and the entire weight bar came crashing down,” he said.
Fortunately, the weight was caught by the machine’s rack, leaving Horsnell with only a few bumps and a bruised ego.
“But the terrifying thing was, I’m lying in a puddle of my sweat and I’m hearing everybody whisper, ‘Is he OK? Do we need to call an ambulance?’ And my first words when I was able to break through the paralysis was, ‘Please don’t call an ambulance!’”
At first, Horsnell blamed the incident on low blood sugar. But then he began slurring his words and had to prop himself up by the elbow or lean against a wall to keep from toppling over while laughing.
“When you fall, the likelihood of catching yourself is basically nil — gravity takes over,” he said. “Lord knows, I busted my noggin a few times, and had a concussion on at least two occasions.”
Horsnell has other common signs of narcolepsy as well, including nightmares and visual and tactile hypnagogic hallucinations, which occur while a person is falling asleep. Typically manifesting as flashing lights, patterns or shapes, such hallucinations are quite common among the general public, experts say. Horsnell’s experience with narcolepsy hallucinations, however, is quite different.
“I feel or I see whatever may be in my dream — like a deceased woman falling on top of my chest,” he said. “I can feel the weight of her body. I can feel her hair tickle my neck. I can see her right in front of my face. It’s quite a nasty experience.”
When he’s extremely tired, these hallucinations can even occur before he gets into bed, Horsnell said.
“I may look into a corner and see a figure that’s not really there, but I see the very clear outline of the shape, and my body is projecting this dream onto the reality,” he said. “I will hear conversations that are taking place that aren’t actually taking place. It can be a little bit disconcerting if you don’t know what’s happening.”
Nightmares plague one-third of people with narcolepsy, while hallucinations are also quite common, said Mundt, who recently conducted a successful pilot study on using cognitive behavioral sleep techniques to control nightmares in people with narcolepsy.
“It’s like your brain is flip-flopping in and out of sleep during both day and night,” she said. “That produces a lot of these symptoms, like the sleep paralysis, sleep hallucinations, and even uncertainty of whether you were asleep or dreaming, because waking up so much creates all this disruption.”
A connection to the flu
Since his symptoms started at age 12, Horsnell saw a pediatrician, an internist and four psychiatrists before visiting a sleep specialist in 2007. Finally, he had a diagnosis — type one narcolepsy with cataplexy, the most common form of the disease. This type of narcolepsy is often confirmed by a spinal tap showing a lack of the neurotransmitter orexin. Also known as hypocretin, orexin plays a key role in regulating appetite and sleep.
“What we think happens is the body’s immune system attacks the part of the brain that makes orexin, so it’s classified as an autoimmune reaction,” Mundt said. “People with type two narcolepsy, however, don’t have a lack of orexin, which we don’t fully understand.”
The gene associated with narcolepsy is present in approximately 25% of the population, but only one in 500 will develop the sleep disorder, according to Narcolepsy Network.
Scientists now believe the trigger for developing narcolepsy may be bacterial and viral infections, such as strep throat or a form of the flu.
“Someone might get the flu, which then starts this auto immune response that ends up basically destroying that part of the brain that makes orexin,” Mundt said. “Then months later, you start to develop narcolepsy because your brain is no longer making orexin.”
There is no drug to treat narcolepsy, but medications can tackle some of the worst symptoms. Horsnell, who believes his narcolepsy was triggered by a bad case of strep throat as a child, has tried most — stimulants to keep him up during the day, along with strong sleep aids at night to stave off constant awakenings.
Sodium oxybate, sold illegally as GHB, is a controlled substance approved by the US Food and Drug Administration to help with the sudden muscle weakness that precedes a catatonic episode. Histamines can help boost levels of orexin in the brain, while certain antidepressants may improve cataplexy as well.
“When you’re having a strong emotional response, if you can take some medications that can blunt or mute that emotion, that can possibly reduce the reaction,” Horsnell said.
Today, Horsnell spends time with his wife and three children, and says he volunteers as a “sleep ambassador” for various narcolepsy associations and advocacy organizations such Project Sleep, the Society for Behavioral Sleep Medicine, the Sleep Research Society, and the American Academy of Cardiovascular Sleep Medicine.
As a trained speaker for Project Sleep’s Rising Voices of Narcolepsy leadership program, he visited the White House in 2023 to raise awareness about narcolepsy and sleep disorders. And he collaborates with both the pharmaceutical industry and scientists like Mundt to help shape research into the condition — he and Mundt recently presented her paper at a conference.
“My journey has been one I take a lot of pride in, but it’s also been a very frustrating and challenging one,” Horsnell said. “If my struggles can help someone come to a quicker diagnosis or better understand living with narcolepsy, that would make some of those struggles fulfilling and worthwhile.”