Migraine and Photophobia: Understanding Light Sensitivity

How common photophobia is in migraine

The large majority of people with migraine report light sensitivity during attacks, and a substantial proportion report it between attacks as well. Published figures vary with the question asked and the population studied, so a single percentage is not quoted here. Light is also one of the most frequently reported attack triggers, although trigger studies are difficult to control. Photophobia severity tends to track overall migraine burden, and it often clusters with sensitivity to sound, smell and touch.

Sources: [5], [4], [6]

The proposed pathway from eye to headache

A key study asked why light worsens migraine pain even in people who are blind. Blind people with migraine who had lost image-forming vision but retained intrinsically photosensitive retinal ganglion cells (ipRGCs) still reported that light intensified their headache; those with no light perception at all did not. In rats, the same study traced ipRGC signals to the posterior thalamus, where they converge on neurons that are also activated by the dura, the pain-sensitive membrane around the brain, and that project to several cortical areas.

This retino-thalamo-cortical convergence is the leading explanation for light-exacerbated headache. It explains why light does not need to be seen clearly to hurt, and why photophobia belongs to the migraine attack rather than to the eye. The route is supported mainly by animal data with human observations behind it, so it is described here as a proposed mechanism.

Sources: [1], [4], [8], [9]

Why colour matters

Not all light is equally aversive. In laboratory testing of people during migraine attacks, white, blue, amber and red light all intensified headache, whereas green light was the least aversive and, at low intensity, reduced pain in a proportion of participants. Recordings in animals suggested that the cone-driven retinal pathway, not only the melanopsin pathway, contributes to these colour differences. Colour-selective discomfort has also been measured in people with migraine between attacks, and in healthy controls to a lesser degree.

These findings motivate interest in wavelength-selective lenses and in green-light environments, but they are laboratory observations. They do not by themselves show that any particular lens or lamp reduces attacks in everyday life.

Sources: [2], [3], [4]

Light sensitivity between attacks

Interictal photophobia is common and often under-recognised. It can drive people to wear dark glasses indoors, which reviews warn against because dark adaptation raises sensitivity further. Interictal photophobia also overlaps with visual discomfort from patterns and flicker, which is why fluorescent lighting and some screens are frequent complaints.

Sources: [6], [7], [5]

Management: what the evidence supports

• Treat the migraine. Acute and preventive treatment prescribed by a physician reduces attack frequency and, with it, photophobia. Light measures are an adjunct.
• During attacks: a dim, quiet room, screens off, and the acute medication plan agreed with your clinician.
• Between attacks: keep exposure to normal light rather than habitual dark glasses indoors; use sunglasses and brimmed hats outdoors; reduce screen brightness and flicker; prefer dimmable, warmer lighting where fluorescent light is a trigger.
• Tinted lenses: a rose tint reduced headache frequency compared with a blue tint in a small randomized trial of 20 children; a 480 nm notch filter did not outperform a 620 nm comparator in a randomized crossover trial of adults with chronic migraine, although both groups improved. Individual benefit is possible; a proven wavelength-specific effect is not established.
• Green light: laboratory data show green is the least aversive colour during attacks; home green-light approaches are under study and are not covered by the sources on this page.

Sources: [7], [10], [11], [2]

Evidence: established versus emerging

Established

• Photophobia is part of the diagnostic picture of migraine and is reported by most people with the condition.
• ipRGCs and melanopsin exist in the human retina and project to the thalamus and other non-image-forming targets.
• Treating the migraine itself is the primary way to reduce migraine photophobia.

Emerging or unresolved

• The ipRGC to posterior thalamus convergence route rests mainly on rat data plus observations in blind migraineurs.
• Colour effects (green least aversive) are laboratory findings; no lens or lamp has been shown in large trials to reduce attacks through colour alone.
• Tinted and notch-filter lenses: small randomized studies with mixed results.

Questions and evidence-based answers

Continue reading

• Photophobia overview
• Melanopsin, ipRGCs and neural responses to light
• Glasses for photophobia and light sensitivity

References

1. Noseda R, Kainz V, Jakubowski M, et al.. A neural mechanism for exacerbation of headache by light. Nature Neuroscience, 2010. PMID 20062053.
2. Noseda R, Bernstein CA, Nir RR, et al.. Migraine photophobia originating in cone-driven retinal pathways. Brain, 2016. PMID 27190022.
3. Nir RR, et al.. Color-selective photophobia in ictal vs interictal migraineurs and in healthy controls. Pain, 2018. PMID 29905657. DOI 10.1097/j.pain.0000000000001303.
4. Burstein R, Noseda R, Fulton AB. Neurobiology of photophobia. Journal of Neuro-Ophthalmology, 2019. PMID 30762717. DOI 10.1097/WNO.0000000000000766.
5. Digre KB, Brennan KC. Shedding light on photophobia. Journal of Neuro-Ophthalmology, 2012. PMID 22330853. DOI 10.1097/WNO.0b013e3182474548.
6. Wilkins AJ, Haigh SM, Mahroo OA, Plant GT. Photophobia in migraine: a symptom cluster?. Cephalalgia, 2021. PMID 33990148. DOI 10.1177/03331024211014633.
7. Katz BJ, Digre KB. Diagnosis, pathophysiology, and treatment of photophobia. Survey of Ophthalmology, 2016. PMID 26875996. DOI 10.1016/j.survophthal.2016.02.001.
8. Hattar S, Liao HW, Takao M, Berson DM, Yau KW. Melanopsin-containing retinal ganglion cells: architecture, projections, and intrinsic photosensitivity. Science, 2002. PMID 11834834.
9. Berson DM, Dunn FA, Takao M. Phototransduction by retinal ganglion cells that set the circadian clock. Science, 2002. PMID 11834835.
10. Good PA, Taylor RH, Mortimer MJ. The use of tinted glasses in childhood migraine. Headache, 1991. PMID 1960058. DOI 10.1111/j.1526-4610.1991.hed3108533.x.
11. Hoggan RN, Subhash A, Blair S, et al.. Thin-film optical notch filter spectacle coatings for the treatment of migraine and photophobia. Journal of Clinical Neuroscience, 2016. PMID 26935748. DOI 10.1016/j.jocn.2015.09.024.