Is It Normal to Sleep With Your Eyes Open? The Hidden Causes You Need to Know

Sleeping With Your Eyes Open: A Sleep Phenomenon You Didn’t Know You Had

Have you ever woken up to the eerie sight of your partner seemingly staring at you in the middle of the night, only to realize they were asleep? If you’ve ever shared a bed with someone with nocturnal lagophthalmos, the experience may have been more than a little unsettling. This strange phenomenon occurs when someone sleeps with their eyes open, and though it’s not exactly a common occurrence, it’s probably more widespread than you might think.

What Is Nocturnal Lagophthalmos?

The medical term for sleeping with your eyes open is lagophthalmos, a condition that refers to the inability to completely close one's eyelids. It’s not a new phenomenon — in fact, historical accounts mention the condition as far back as the second and third centuries BCE. Chinese military general Zhang Fei is said to have escaped an assassination attempt because his enemies mistakenly believed he was awake. This legend highlights the potential intrigue and mystery that surrounds this condition.

Lagophthalmos comes in a few different forms, from mild cases where only a tiny gap remains, to more severe cases where the eyes are wide open throughout the night. It can occur for several reasons, some of which are related to anatomical variations, while others involve underlying medical conditions. Regardless of the cause, nocturnal lagophthalmos raises a few interesting questions. While the condition is rarely serious, it can lead to complications that impact the health of your eyes and your quality of sleep.

How Common Is Nocturnal Lagophthalmos?

You might be surprised to learn that sleeping with your eyes open is more common than it appears. Although it’s often considered a rare condition, some studies estimate that around 5-20% of adults experience nocturnal lagophthalmos to varying degrees. Interestingly, many of those affected may not even realize they have it. Most people with this condition fall asleep and wake up without any awareness that their eyes stayed open the entire time.

The 2019 case report on the subject noted that not much is understood about the condition’s prevalence or specific causes. This is partially due to the fact that many people with nocturnal lagophthalmos may never seek treatment or even notice the condition. As a result, estimates on its frequency vary, but researchers believe the true rate of occurrence is probably higher than we think.

What Causes Nocturnal Lagophthalmos?

The reasons why some people sleep with their eyes open vary. Here are some of the more common causes:

1. Facial Nerve Paralysis: Paralysis of the facial nerve can affect the ability of the eyelids to close fully. Conditions such as Bell’s palsy or other forms of facial nerve dysfunction can lead to incomplete eyelid closure, especially during sleep.
2. Eye Injuries: Damage to the eye, eyelid, or the surrounding facial muscles can disrupt the normal function of the eyelids.
3. Anatomical Differences: Certain individuals may have physical characteristics, like proptosis (bulging eyes), which makes it difficult for their eyelids to cover their eyeballs entirely, particularly when they sleep. Graves’ disease, a thyroid-related disorder, is often a culprit here.
4. Neurological Disorders: Some neurological conditions, such as Parkinson’s disease, can lead to involuntary muscle weakness or dysfunction, which may prevent the eyelids from fully closing during sleep.
5. Congenital Conditions: In rare cases, lagophthalmos is present from birth. These individuals may have eyelid abnormalities that affect the natural function of the eyelids.

Though the causes can vary widely, the underlying issue is generally related to incomplete eyelid closure, which leads to the eyes remaining exposed for prolonged periods while sleeping.

Is Nocturnal Lagophthalmos Harmful to Your Health?

While it’s generally not a dangerous condition, nocturnal lagophthalmos can lead to several issues that may affect both your eye health and overall well-being.

The primary concern for people who sleep with their eyes open is the potential for dry eyes. The eyelids play an important role in protecting the eyes from environmental factors like dust, wind, and bacteria. They also help spread tear film across the surface of the eye, keeping it moist and comfortable.

When the eyes remain open, this protective mechanism is compromised, and the tear film can evaporate, leaving the eyes dry and irritated. Over time, this can result in dry eye disease — a condition that affects up to 50% of the global population to varying degrees.

Dry Eye Symptoms Include:

• Increased eye watering (which may sound paradoxical, but the body produces more tears to compensate for dryness)
• A sensation of something in the eye, such as grit or foreign particles
• Pain or irritation, especially when waking up in the morning

While most people with dry eye disease don’t experience severe, lasting damage to the surface of the eye, there is still a risk. Chronic dryness can lead to corneal damage if not addressed. This could increase the risk of eye infections, as a dry eye is more susceptible to irritation and infection.

How to Manage Nocturnal Lagophthalmos

If you suspect that you or someone close to you may be experiencing nocturnal lagophthalmos, it’s important to seek guidance from an eye doctor. While the condition is typically not life-threatening, there are ways to alleviate its effects and protect the eyes during sleep.

1. Lubricating Eye Drops or Ointments: Using artificial tears or thicker lubricating ointments before bed can help keep the eye surface hydrated and reduce the risk of irritation.
2. Eyelid Taping: Some people use a medical adhesive tape to gently tape their eyelids closed at night. This ensures that the eyelids fully cover the eyes during sleep, preventing dryness and irritation.
3. Humidifier: Adding a humidifier to the bedroom can help maintain moisture in the air, preventing excessive evaporation of the tear film during sleep.
4. Addressing Underlying Conditions: If lagophthalmos is caused by an underlying medical condition such as facial nerve paralysis or Graves' disease, seeking treatment for that condition can help resolve or mitigate the symptoms of nocturnal lagophthalmos.

In most cases, nocturnal lagophthalmos is manageable, and treatment focuses on protecting the eyes from excessive dryness and irritation. However, it's always best to consult with a healthcare provider to develop an appropriate plan tailored to your specific needs.

When to See a Doctor

If you notice symptoms such as excessive dryness, irritation, or discomfort in your eyes upon waking up, or if you think you may be sleeping with your eyes open, it’s essential to seek professional advice. An eye doctor can assess the condition and suggest the best treatment options.

In rare cases, if left untreated, dry eye disease can lead to more severe complications, including vision impairment or chronic infections. So, while it’s unlikely to be a major concern, keeping the eyes well-lubricated and managing any underlying conditions is important for maintaining optimal eye health.

Final Thoughts

Though sleeping with your eyes open may seem like a quirky, rare phenomenon, it’s surprisingly common — and typically harmless. From historical accounts of military leaders avoiding assassinations to modern-day sleep habits, nocturnal lagophthalmos has intrigued many over the years. While it can lead to discomfort and dry eye symptoms, it’s usually manageable with proper care and attention. If you or someone you know sleeps with their eyes open, it’s worth investigating further to prevent any potential complications.