Eye Pain and Headache on One Side: Causes and Care

What causes pain behind one eye with a headache?

Several distinct conditions can produce this combination. They vary enormously in severity and urgency:

Understanding which pattern fits your experience guides what kind of evaluation you need.

Migraine: the most common cause

Migraine frequently causes pain that is felt at or behind one eye, even though the pain originates in nerve pathways in the brain rather than in the eye itself. Classic migraine features include:

• Moderate to severe throbbing or pulsating pain, usually one-sided.
• Nausea or vomiting.
• Sensitivity to light (photophobia) and sound (phonophobia).
• Pain that worsens with physical activity.
• In some people: a visual aura before the headache (zigzag lines, blind spots, or flickering lights) lasting 20–60 minutes.

Migraine does not cause redness of the eye, halos around lights, or a fixed dilated pupil — features that point toward a different diagnosis 1Ref 1Silberstein SD, Holland S, Freitag F, Dodick DW, Argoff C, Ashman E (2012).Evidence-based guideline update: Pharmacologic treatment for episodic migraine prevention in adults: Report of the Quality Standards Subcommittee of the American Academy of Neurology and the American Headache Society.Migraine as the most common primary headache disorder with periorbital pain distribution; clinical features distinguishing migraine from other headache types2Ref 2Ailani J, Burch RC, Robbins MS; Board of Directors of the American Headache Society (2021).The American Headache Society Consensus Statement: Update on integrating new migraine treatments into clinical practice.Clinical classification of cluster headache and migraine, distinguishing autonomic features of cluster headache (tearing, ptosis, nasal congestion) from migraine.

Cluster headache: severe and unmistakable

Cluster headache is one of the most painful headache disorders known. The pain is severe, strictly one-sided, and concentrated around or behind the eye. What distinguishes it from migraine is the autonomic features on the same side as the pain:

• Eye tearing and redness.
• Nasal congestion or runny nose.
• Drooping eyelid (ptosis) or small pupil (miosis).
• Restlessness — unlike migraines, people with cluster headache cannot lie still.

Attacks last 15–180 minutes and occur in clusters of weeks to months, followed by remission. They often wake people from sleep at the same time of night. Anyone with this pattern should be evaluated by a neurologist or headache specialist, as effective treatments exist 1Ref 1Silberstein SD, Holland S, Freitag F, Dodick DW, Argoff C, Ashman E (2012).Evidence-based guideline update: Pharmacologic treatment for episodic migraine prevention in adults: Report of the Quality Standards Subcommittee of the American Academy of Neurology and the American Headache Society.Migraine as the most common primary headache disorder with periorbital pain distribution; clinical features distinguishing migraine from other headache types2Ref 2Ailani J, Burch RC, Robbins MS; Board of Directors of the American Headache Society (2021).The American Headache Society Consensus Statement: Update on integrating new migraine treatments into clinical practice.Clinical classification of cluster headache and migraine, distinguishing autonomic features of cluster headache (tearing, ptosis, nasal congestion) from migraine.

Acute angle-closure glaucoma: a true emergency

This is the diagnosis that cannot be missed. Acute angle-closure glaucoma occurs when the drainage angle of the eye suddenly closes, causing intraocular pressure to spike rapidly. The resulting combination of eye pain and headache can mimic migraine — but the eye-specific features distinguish it:

• Halos around lights (caused by corneal edema from elevated pressure).
• Blurred or cloudy vision in the affected eye.
• A mid-dilated, fixed pupil that does not constrict in light.
• The eye may feel hard to the touch.
• Nausea and vomiting are common.
• Redness of the eye.

This is an ocular emergency. Without treatment within hours, irreversible vision loss can occur. If you have headache with eye pain accompanied by halos around lights and blurred vision, go to an emergency department immediately or call an ophthalmologist for same-day evaluation 3Ref 3Gedde SJ, Chen PP, Muir KW, Vinod K, Lind JT, Wright MM, Li T, Mansberger SL; American Academy of Ophthalmology Preferred Practice Pattern Glaucoma Panel (2021).Primary Angle-Closure Disease Preferred Practice Pattern.Acute angle-closure glaucoma presenting with eye pain, headache, halos around lights, blurred vision, and nausea; time-critical nature of treatment to prevent permanent vision loss.

Who evaluates eye pain with headache?

The specialist depends on what the pattern suggests:

• Migraine or cluster headache — a neurologist or headache specialist manages these conditions. Primary care can initiate evaluation and treatment.
• Acute angle-closure glaucoma — this requires immediate assessment by an ophthalmologist or in an emergency department.
• Sinusitis — a primary care clinician or ENT can evaluate and treat.
• Uncertain diagnosis — if the pattern is unclear, start with your primary care clinician, who can assess the clinical picture and coordinate the right referral.

Gale's primary care clinicians can evaluate new-onset eye pain with headache, determine urgency, and connect you with the appropriate specialist.