Understanding Photophobia: Why Light Sensitivity Happens & How to Treat It

by The Allay Team

Most people have experienced light sensitivity in some way shape or form — even if it’s just squinting painfully in the bright sunshine. But what happens when even the light we depend on to carry out daily tasks becomes too much to bear? For some people, such a degree of sensitivity, called photophobia, is a harsh reality that makes activities such as work, watching television, or enjoying time outside nearly impossible.

If you’re one of the many people who suffer from photophobia - perhaps because of an underlying condition like migraine - you already know how disruptive it can be. You’re likely also well aware of how few treatments are available specifically for your light sensitivity. In this article, we’ll explore what photophobia is, what causes it, and how a new treatment - powered by groundbreaking new research - is enabling accessible, affordable relief while letting you keep a light on.

What is photophobia?

Simply put, photophobia is a sensitivity to the presence of light that results in pain or discomfort. It is generally looked at as a symptom as opposed to a condition, and can be temporary or chronic in nature, depending on the cause. In medical literature, you might see photophobia referred to in four different contexts:

Abnormal sensitivity to light
Ocular discomfort (photo-oculodynia)
Exacerbation of headache by light
General aversion to light

The term itself might strike you as odd because of the inclusion of “phobia” — after all, we associate the word “phobia” with a deep-rooted fear. You might even be pretty familiar with scientific names like acrophobia (fear of heights), glossophobia (fear of public speaking), or if you have a thing for so-bad-it’s-good movies from the early ‘90s, arachnophobia (fear of spiders).

An intense fear can definitely be a phobia, but the term phobia casts a bit of a wider net, as it can also mean an extreme aversion to something. So while you’re likely not terrified of light if you are sensitive to it, it’s a phobia because you are physiologically averse to it — it causes you pain or discomfort. In this sense, the most literal definition of photophobia is “light aversion.”

What are symptoms of photophobia?

Some symptoms of photophobia will seem obvious, but there are others you may have never associated with light sensitivity. As we explore the physiological connection between light and pain, you’ll see why some of the more surprising symptoms (like anxiety and dizziness) are just as connected to light sensitivity as discomfort of the eyes.

Here are some of the primary photophobia symptoms most people experience:

Eye pain
Headache
Migraine attack
Straining your eyes or squinting
Intolerance of light (extreme light sensitivity)
Anxiety
Excessive blinking
Watery eyes

What causes photophobia?

The question here is two-pronged. First, we need to know what exactly is going on at the physiological level when photophobia occurs. But it’s also important to understand which conditions or illnesses can cause photophobia. Both are equally important questions when it comes to understanding what makes eyes sensitive to light and developing effective treatments to prevent it from happening.

The physiology has long been a mystery.

If there’s something affecting our vision, we have a tendency to assume that our eyes are to blame. When it comes to photophobia, that’s not always the case. There is something happening at the physiological level, but it’s generally not a manifestation of the eyes — often, photophobia causes are byproducts of the central nervous system.

Scientists are yet to identify the exact physiological mechanisms that cause photophobia with 100% certainty, but new research is ripe with groundbreaking discoveries that have put medicine on the path to demystifying it once and for all.

Scientists have discovered a probable pathway.

In 2010, Dr. Rami Burstein and his research team published a paradigm-shifting study pointing to a previously unknown pathway by which light exacerbates migraine pain. To execute the research, the team worked with blind migraine patients, who they eventually found could be split into two groups: those who could sense light and those who couldn’t. Interestingly, the presence of light still had a worsening effect on the migraine symptoms of those who could sense it — whereas with the other group, it had no effect at all. Neither group could receive visual information via the rods and cones that form images, so how could this be?

Dr. Burstein found the answer in a non-image-forming pathway, lined with light-regulated neurons. This pathway originates not at rods and cones, but rather at intrinsically photosensitive retinal ganglion cells. It impacts more than just vision, extending to other areas of the brain tied to a variety of cognitive functions such as clarity of thinking, memory recall, emotional regulation, and sensory perception.

Does all light make photophobia worse?

Building on his discovery of the retinal pathway, Dr. Burstein led additional research over the next five years to determine if different colors of light interact differently with photophobia. By exposing participants to wavelengths of white (regular room light), blue, green, amber, and red lights during a migraine, he and his team found that all colors of light make photophobia worse except one. Only a single, narrow band of green light actually soothed light sensitivity and migraine activity. On the other hand, red and blue light proved to be the most exacerbating wavelengths.

This is because red and blue light create the largest electrical signals in the eyes, while pure green light creates the smallest signals. In generating smaller signals, this green light triggers less neuronal activity in the retinal pathway that connects light to pain. In a 2020 study, researchers even found that this band of green light may help relieve chronic pain in those with fibromyalgia, which makes sense given that photophobia is intimately tied to pain sensation.

Which conditions can cause photophobia?

There are dozens of conditions that cause photophobia, but some of the most common are:

Migraine
Blepharospasm
Traumatic brain injury
Meningitis
Dry eyes
Conjunctivitis
Ocular inflammation
Anxiety disorder
Depression
Fibromyalgia
Lyme Disease
Multiple Sclerosis
COVID-19
Glaucoma

How do you treat photophobia?

There is currently no pharmaceutical photophobia treatment, which makes sense given that scientists don’t yet fully understand the physiological mechanisms that cause photophobia from condition to condition. Nevertheless, physicians do understand that the question of how to treat photophobia is best answered by managing the underlying cause. For instance, fewer migraine attacks will mean less light sensitivity, so a doctor may prescribe migraine medication, which in turn may lessen the frequency and severity of photophobia for a migraine patient.

Fortunately, the absence of tailored pharmacological treatment doesn’t mean all hope is lost. In fact, some of the research mentioned earlier in this article has paved the way for safe, effective, and accessible treatment that you can turn to when light sensitivity strikes.

Find relief in narrow-band green light.

If you’ll remember from earlier, we know that narrow-band green light can soothe light sensitivity, thanks to Dr. Rami Burstein’s research. In fact, he suggested that creating a green light device could bring much-needed relief to the millions of people who suffer from migraine photophobia. By working closely with Dr. Burstein, we’ve created that very device, so that photophobia doesn’t have to mean putting life on hold.

The Allay Lamp makes it possible to take the soothing power of this patented green light with you wherever you go. Easily dimmable, it’s bright enough to provide the light you need to continue working or reading — without the discomfort or pain that normally comes from bright light. It also makes a great bedside lamp to help wind down and relax at the end of the day. But most importantly, it’s completely safe, with zero unwanted side effects.

Keep these additional tips in mind.

Even when using your Allay Lamp, you can take these steps to help keep photophobia at bay:

Find ways to reduce your screen time throughout the day.
Use UV-blocking sunglasses when outdoors or in your car.
Wear a billed hat to shade your eyes from indoor lights.
Avoid migraine triggers or any triggers of your underlying condition.
Fix flickering lights as soon as possible.
Take time to rest your eyes and unplug from all screens an hour or more before bed.
Install available screen-filtering apps on your phone.
Be honest with friends and family instead of trying to tough it out.

Let there be light.

Science has long been in the dark when it comes to photophobia, leaving those who experience light sensitivity without the relief and confidence needed to seize each day. However, thanks to the discovery of a number of previously unidentified retinal connections with the brain and the soothing power of narrow-band green light, there’s a light at the end of the tunnel at long last. The Allay Lamp puts the power of that patented green light in the palm of your hand, so you can live life in the light.

Meet the Allay Lamp →

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