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Fatal Familial Insomnia: Symptoms, Diagnosis, and Treatment

Last Updated on November 1, 2023

Written by Jill Zwarensteyn

Although many folks experience insomnia, most are able to get some amount of shut-eye.
However, a rare and serious condition known as Fatal Familial Insomnia causes people to lose the ability to sleep over a period of time.
As humans, we need sleep to function. As a result, the ramifications of this disease are deadly.
In this article, we will go into detail about Fatal Familial Insomnia, including the symptoms, who is at risk, and what to do if you have it.

What is Fatal Familial Insomnia?

Fatal Familial Insomnia[1] (FFI) is a degenerative brain disorder that inhibits a person’s ability to fall asleep. According to experts, insomnia symptoms continue to worsen over time. People with Fatal Familial Insomnia can also experience impairments with their autonomic nervous system, which is responsible for automatic bodily functions such as your heartbeat, breathing, or sweating.

How Do You Get It?

prion protein (PrP), an active protein in the brain.
When the gene sends abnormal signals, it can lead to malformed—and toxic—prions. The accumulation of these toxic prions can cause a decrease in nerve cells, which is what causes insomnia and associated symptoms.
People inherit FFI in a gene pattern known as autosomal dominant. In our DNA, we inherit two copies of each gene.
Autosomal refers to when the particular gene is found on a numbered, non-sex chromosome, and dominant means that only a single copy of a mutated gene is needed to carry the disease. Conversely, recessive genetic disorders need two mutated copies to pass along a disease.
Want to know more? Find out how genes influence your risk of insomnia.

Sporadic Fatal Insomnia

Not all cases of fatal insomnia are inherited, though. Specifically, scientists say that sometimes a person can develop a spontaneous genetic mutation affecting the prion protein, known as Sporadic Fatal Insomnia[2]. Both the sporadic form and familial insomnia are rare human prion diseases.
Additionally, prion diseases can result from an individual’s environment. For example, one way to acquire a prion disease is through iatrogenic exposure, which is when your condition stems from medical care. Additionally, some people have also acquired prion deterioration through contaminated beef consumption.


Scientists officially named this rare disease Fatal Familial Insomnia in 1986. An Italian family[3], who had the disease passed down through generations over 200 years, provided these researchers with a substantial amount of details when one of the members, Silvano, decided to go public with the family history of this condition.
The scientists were able to study Silvano and his symptoms during his last few months alive. Unfortunately, he passed away in 1984 at the age of 53, but his contributions to the study of FFI remain impactful to this day.


Fatal Insomnia symptoms usually begin between the ages of 40 and 60. However, this can vary, as some reported cases have seen people in their 20s develop symptoms. According to the National Center for Advancing Translational Sciences, the following symptoms are common signs of Fatal Familial Insomnia.


Insomnia is one of the primary symptoms of this disease. We mentioned earlier that Fatal Familial Insomnia leads to a loss of nerve cells – or neurons – in the brain. The neuron loss is primarily centered in the thalamus[4], the part of the brain that regulates the body’s natural sleep-wake cycle. Thus, FFI’s effect on the thalamus is what ultimately causes people to experience this extreme insomnia.
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Cognitive Impairment

If you’ve experienced even just one night of sleep deprivation, you are probably all too familiar with how it leaves you feeling as though you are in a brain fog the following day. Unfortunately, after multiple nights of little to no sleep, this only continues to worsen. Much like regular insomnia, Fatal Familial Insomnia is linked to diminished cognitive abilities, including difficulty thinking and concentrating.

Short-Term Memory Loss

Another troublesome side effect of Fatal Familial Insomnia is short-term memory loss, which is when you can’t recall something you learned or experienced recently, like learning someone’s name 20 minutes ago. On the other hand, long-term memory reflects information stored in the brain over long periods of time, such as childhood memories.

Weight Loss

Someone with Fatal Familial Insomnia may also experience significant weight loss, even if their food consumption increases. For instance, a 1999 study[5] on the effects of Fatal Familial Insomnia in five members of an Austrian family found that extreme weight loss was an early symptom in all five individuals. One patient, a 25-year-old man, experienced a weight loss of more than 20 kilograms – or about 40 pounds – in only six months.

Poor Coordination

Difficulty coordinating your body movements is another one of the common symptoms of Fatal Familial Insomnia. In some cases, a person may experience a complete loss of coordination, formally known as ataxia[6]. Loss of coordination reveals itself in various ways, including balance, walking, speaking, writing, swallowing, and vision.
People who have had a stroke, multiple sclerosis (MS), a brain tumor may also develop ataxia. When this happens, it is known as acquired ataxia.

High Blood Pressure

Blood pressure measures the pressure of your blood against the walls of your arteries. When that pressure grows too much, this is referred to as high blood pressure[7] – or hypertension.
Health experts say many individuals may not feel the effects of high blood pressure apart from headaches, shortness of breath, or nosebleeds. However, high blood pressure is a dangerous health condition because it could eventually lead to serious health complications such as heart attack, stroke, aneurysm, heart failure, impaired blood vessels, metabolic syndrome, cognitive difficulties, and dementia.

Unable to Maintain Body Temperature

Individuals with Fatal Familial Insomnia can also have trouble maintaining stable, healthy body temperature patterns. According to research[8], Fatal Familial Insomnia can affect a person’s circadian rhythms, natural body clocks that regulate sleep-wake patterns.
Circadian rhythms prepare the body for sleep, and an example of this is lowering the body’s core temperature. However, individuals with Fatal Familial Insomnia typically have elevated core body temperatures, which may further explain their disconnect from sleep.

Profuse Sweating and Crying

An individual may also see an increase in the production of sweat and tears resulting from Fatal Familial Insomnia. Earlier, we mentioned Silvano, an Italian man who had Fatal Familial Insomnia and a family history of this disease. According to the scientists, excessive sweating was one of the other symptoms he he developed in addition to insomnia.

Diagnosing Fatal Familial Insomnia

To diagnose FFI, a doctor will first review your symptoms. From there, the physician may perform a clinical exam and refer to a sleep specialist to undergo a sleep study – or polysomnography[9].
Polysomnography is used to help diagnose various sleep disorders. During this test, the sleep specialist will hook you up to equipment that measures your brain waves, blood oxygen levels, heart rate, breathing, and leg and eye movements while you are asleep. Sleep tests can either be provided in a clinic or at home.
Imaging tests may also be a step in the diagnosing process. These types of tests help provide a visual understanding of what is happening inside the body.
Since this is an inherited disease, genetic testing may confirm whether the individual has Fatal Familial Insomnia. In some cases, the person may already know a family member who has had this condition. Genetic testing involves looking for variations or mutations in your DNA.

Treatment Options

There is no known cure for Fatal Familial Insomnia. As a result, treatment of this disease focuses on mitigating symptoms to help the individual feel as comfortable as possible.
According to the National Center for Advancing and Translation Sciences, a person with FFI may see a team of specialists, including a neurologist, medical geneticist, and social worker. Family counseling is also highly encouraged. FFI’s rare status means you may need to reach out to universities, national, or even international outlets to find healthcare professionals who specialize in this field.

Emerging Science

However, scientists are continuing in their search for helpful treatment options for FFI. For example, doctors Joyce Schenkein, Ph.D. and Pasquale Montagna, MD, found that the drug Gamma-hydroxybutyrate (GHB) successfully provided three hours of slow-wave (deep) sleep for a person with FFI for up to 14 months.
In clinical trials[10], small molecule compounds showed mixed results for delaying the progression of the disease. The compounds included pentosane polysulfate, quinacrine, and amphotericin B. However, animal tests with these molecules saw more success.
Currently, an ongoing study is looking to see if the drug doxycycline, which is normally used to treat bacterial infections, could be a preventative treatment[11] for Fatal Familial Insomnia. The study participants have a genetic risk for developing FFI and will be taking doxycycline for ten years.

Other Neurological Sleep Disorders

Fatal Familial Insomnia is one type of neurological sleep disorder. However, there are additional sleep disorders caused by neurological issues[12].

Central Nervous System Hypersomnia

Central nervous system hypersomnia, also known as Idiopathic CNS Hypersomnia, is when an individual experiences excessive sleepiness and prolonged sleep durations. However, the condition is not caused by another sleep disorder.

Central Sleep Apnea

Central sleep apnea is a disorder in which a person’s breathing continually starts and stops while asleep. More specifically, the brain cannot send the correct signals to the airway muscles, which causes gaps in breathing. Another form of sleep apnea, obstructive, is more common due to a physical blockage in the airway’s path.

Circadian Rhythm Disorders

Circadian rhythm disorders occur when the body’s internal clock regulating the sleep-wake cycle does not work properly. As a result, people with these disorders have trouble falling asleep, staying asleep, or waking up too early.


Narcolepsy is characterized by extreme tiredness and suddenly falling asleep. Additional symptoms can include muscle tone toss, sleep paralysis, rapid eye movement (REM) sleep changes, and hallucinations.
Experts do not know the exact cause of this disorder but say that people with narcolepsy[13] often have low Hypocretin levels in the brain. Hypocretin is a chemical that is responsible for controlling wakefulness and REM sleep.


Parasomnias are unusual behaviors that interrupt sleep. Examples of this include sleepwalking, talking in your sleep, and sleep paralysis. Parasomnias[14] may result from neurological sleep disorders like narcolepsy and circadian rhythm disorders.

REM Sleep Behavior Disorder

REM sleep behavior disorder involves the sleeper acting out bad dreams. Normally, humans lose their ability to move during REM sleep, when dreaming occurs, as a means to keep them safe. Mayo Clinic[15] experts hypothesize that REM sleep behavior disorder may be linked to neurological conditions like Lewy body dementia, Parkinson’s disease, or multiple system atrophy.

Frequently Asked Questions

Is it common?

Fatal Familial Insomnia is a highly rare disease. The National Center for Advancing and Translational Sciences reports that only 70 families are on record for having FFI. However, the exact number of individuals with this disease remains unknown.

How long can you survive FFI?

Unfortunately, without a cure, FFI is fatal to those who have it. The life expectancy for individuals with this disease ranges from six months to three years, though some experts say the minimum is closer to seven months.
Fatal Familial Insomnia is broken down into four stages[16]. However, these timelines can vary according to each individual’s particular case. Therefore, consider this a general blueprint timeline.

Stage 1

During the initial stage, the individual will begin to experience acute insomnia, which will worsen over the following few months. The sleeplessness is expected to lead to psychiatric side effects such as phobias, paranoia, and panic attacks. Lucid dreaming may also occur.

Stage 2

The following stage typically lasts for about five months. During this time, the individual’s sleep capability will continue to decline, and their psychiatric symptoms will worsen. Additionally, the deterioration of autonomic functions may cause hyperactivity of the sympathetic nervous system. Examples of this hyperactivity can include increased heart rate, rapid breathing, and high blood pressure.

Stage 3

The third stage usually goes on for about three months. Stage 3 tends to see a complete lack of sleep and disruptions to the individual’s sleep-wake cycle.

Stage 4

The fourth and final stage of Fatal Familial Insomnia will typically last six months or longer. At this time, the individual will see the swift collapse of their cognitive abilities and the emergence of dementia.
Furthermore, they will likely no longer be able to move on their own and have speech problems. Next, the individual will likely enter into a coma shortly before death.

What’s the difference between FFI and Insomnia?

Fatal Familial Insomnia and traditional Insomnia may share similar titles, but the two have significant differences. FFI is a rare neurological disorder that an individual inherits from a family member. Insomnia[17], on the other hand, is a sleep disorder that is typically caused by lifestyle factors.
However, certain medical conditions, mental health issues, and advanced again can also lead to insomnia. Lastly, insomnia may also be a byproduct of other sleeping disorders such as sleep apnea and restless legs syndrome.
Lifestyle choices that can cause insomnia include stress, travel, and work schedules, bad sleeping habits, smoking, going to bed full, and consuming caffeine and alcohol. Additionally, women and people over the age of 60 are at a higher risk of insomnia.
Unlike FFI, insomnia is more common, and it is a treatable condition. Some people may take sleeping medications. However, doctors may advise simple lifestyle changes to alleviate an individual’s insomnia.
In addition to limited or sleep, FFI and insomnia share some other symptoms as well. For example, people with insomnia can also experience impaired cognitive abilities and high blood pressure.

Sources and References:

  • [1] “Fatal familial insomnia”, National Center for Advancing Translational Sciences, November 2020
  • [2] Jennifer L. Blase MPH, Laura Cracco PhD, Lawrence B. Schonberger MD, Ryan A. Maddox PhD, Yvonne Cohen BS, Ignazio Cali MS, Ermias D. Belay MD, “Sporadic Fatal Insomnia in an Adolescent”, National Library of Medicine
  • [3] “A ‘family curse’: First insomnia, then death”, CNN, 2017
  • [4] Zalan Kahn, Pradeep C.  Bollu, “Fatal Familial Insomnia”, National Library of Medicine
  • [5]  G. Almer, J. A. Hainfellner, T. Brücke, K. Jellinger, R. Kleinert, G. Bayer, O. Windl, H. A. Kretzschmar, A. Hill, K. Sidle, J. Collinge, H. Budka, “Fatal familial insomnia: a new Austrian family”, Oxford Academic
  • [6] “High blood pressure (hypertension)”, National Health Service, July 2021
  • [7] “Self Management of Fatal Familial Insomnia. Part 1: What Is FFI?”, Mayo Clinic, 2006
  • [8] Joyce Schenkein PhD, Pasquale Montagna MD, “Polysomnography (sleep study)”, National Library of Medicine, December, 2021
  • [9] “Polysomnography (sleep study)”, Mayo Clinic
  • [10] Jennifer T. Burchell, Peter K. Panegyres, “Prion diseases: immunotargets and therapy”, National Library of Medicine, 2016
  • [11] Gianluigi Forloni, Mauro Tettamanti, Ugo Lucca, Yasmin Albanese, Elena Quaglio, Roberto Chiesa, Alessandra Erbetta, Flavio Villani, Veronica Redaelli, Fabrizio Tagliavini, Vladimiro Artuso,Ignazio Roiter, “Preventive study in subjects at risk of fatal familial insomnia: Innovative approach to rare diseases”, National Library of Medicine, 2015
  • [12] “Neurology – Sleep Conditions”, Penn Medicine
  • [13] “Narcolepsy”, Mayo Clinic, November 2020
  • [14] “Parasomnias & Disruptive Sleep Disorders”, Cleveland Clinic, April 2021
  • [15] “REM sleep behavior disorder”, Mayo Clinic, January 2018
  • [16] “Fatal Familial Insomnia”, Stat Pearls, July 2021
  • [17] “Insomnia”, Mayo Clinic, October 2016
Jill Zwarensteyn

Jill Zwarensteyn


About Author

Jill Zwarensteyn is the Editor for Sleep Advisor and a Certified Sleep Science Coach. She is enthusiastic about providing helpful and engaging information on all things sleep and wellness.

Combination Sleeper