Headache behind the left eye: what to know

Headache behind the left eye can have several causes, so note its pattern and accompanying symptoms before choosing care. Pain may feel dull, throbbing, stabbing, or pressure-like. Bright light, screen use, nasal congestion, fever, poor sleep, missed meals, heat, or too little fluid can help explain the timing.

The location alone does not identify a diagnosis. Migraine can cause one-sided pain with nausea or sensitivity to light and sound. A cluster-type headache can cause severe pain around one eye with tearing, a blocked or runny nostril, or restlessness. Sinus inflammation may add facial pressure and congestion; see information about Allergic Rhinitis, Chronic Sinusitis, Common Cold, or COVID-19 when those symptoms are present. Eye strain, an uncorrected vision problem, jaw tension, and neck muscle tension can also refer pain toward the eye.

Rest in a quiet, dim room and take a break from screens. Drink fluids gradually, eat if you have missed a meal, and try a cool compress over the closed eyelid or forehead. Keep a brief record of onset, duration, triggers, nausea, visual changes, and medicines taken. Use an over-the-counter pain reliever only if it is normally safe for you and follow its label; a pharmacist can check interactions and medical conditions. Heat Exhaustion and Dehydration can both cause headache, so move to a cool place and replace fluids if heat or sweating preceded it.

Seek urgent help for a sudden, extreme headache; new weakness, confusion, fainting, trouble speaking, or loss of balance; a painful red eye; sudden vision loss; repeated vomiting; high fever with a stiff neck; or headache after a significant head injury. Arrange a medical review if this is a new pattern, keeps returning, steadily worsens, follows an eye injury, or does not settle with usual measures. A clinician can examine the eye, nerves, sinuses, and neck and decide whether further tests are needed.

Ask: What features suggest migraine, sinus pressure, eye strain, or another cause? Should my vision and eye pressure be checked? Which pain medicine is suitable with my current conditions and medicines? What changes should prompt urgent review? Bring your symptom record, including whether the left-sided pain follows sleep loss, heat, exertion, congestion, or screen use.