Many people have the unpleasant experience of waking up with dry eyes. Why is that, and what can be done about it?
Dry eye is generally caused by either inadequate tear production, or a problem with the tear film that leads to it evaporating too quickly. So why would people get dry eye overnight?
Nocturnal lagophthalmos is the condition where the eyelids don’t fully close while sleeping. It is thought to be caused by a weakness in the seventh cranial nerve (also known as the facial nerve), which can be caused by: injury to the cerebellar artery (which delivers blood to the face), jaw or skull trauma, or Bell’s Palsy (sudden but generally temporary weakness in facial muscles.)
The eyelids not closing while asleep can negatively impact the tear film (the layer of fluid which covers the eyes), and, if the eyes are exposed to air without the proper blinking, a process which reapplies tears to keep the eyes lubricated, they can become dry.
A 2020 study found that this condition, in addition to causing dry eye upon awakening, nocturnal lagophthalmos can worsen dry eye symptoms and reduce the quality of your sleep. This research also found that an overstimulation of the Muller’s muscle (one of the two muscles which keep the eye open while you are awake) can cause this condition.
Other risk factors for nocturnal lagophthalmos include younger age, and shift work.
There are few things you can do to deal with your NL. These include:
Relaxing activities, like the warm bath, can increase your parasympathetic activity, which regulates the “rest and digest” function and decreases sympathetic activity prior to falling asleep. This may also reduce the stimulation of the Muller’s muscle.
Taping the eyelids closed physically keeps your eyes covered, which should help keep them better lubricated.
Other standard treatments for dry eye can be effective at treating symptoms from nighttime dry eye, such as artificial tears.
If you experience dry eye upon waking up, it is likely caused by nocturnal lagophthalmos. In addition to the suggestions listed above, a doctor can provide you with additional guidance on what to do to treat and resolve this issue. If you’d like to schedule an appointment for a consultation at American Family Vision Clinic, you can contact us at (360) 491-2121.