Waking up with blurry vision in one eye can be unsettling. This common occurrence stems from various underlying reasons, ranging from minor, temporary issues to more significant conditions requiring prompt medical attention. Understanding causes helps determine appropriate action.
Immediate Steps to Take
If one eye is blurry, remain calm. Blink several times; this can clear minor surface issues. If blurriness persists, close the eye briefly, then reopen it. Check for foreign objects like a stray eyelash.
Moisten the eye by blinking or using artificial tears to alleviate dryness. Note any accompanying symptoms like pain, redness, or discharge. If blurriness doesn’t resolve within a few minutes, consider its underlying cause.
Common Temporary Causes
Many instances of unilateral blurry vision upon waking are temporary. Dry eyes are a frequent cause, especially after sleep when tear production decreases or if eyes are slightly open, causing tear film evaporation. This dryness can make the cornea uneven, distorting light and blurring vision.
Sleeping in contact lenses can cause temporary blurriness by limiting oxygen flow to the cornea, leading to swelling. Lenses can also dry out overnight, irritating the eye or altering its surface. Minor eye irritation from allergens, dust, or foreign particles can also induce temporary blur, as the eye’s response may involve slight swelling or tear film changes.
Sleeping position can contribute to temporary blurriness. Pressure on one eye from sleeping face-down can temporarily alter its shape or blood flow, causing transient blurriness that usually dissipates quickly. Eye fatigue from extended screen time or reading before bed can also cause temporary blurriness due to muscle strain.
Potentially Serious Causes
While many cases of unilateral blurry vision are benign, certain conditions warrant professional evaluation. A corneal abrasion, a scratch on the eye’s clear front surface, can significantly affect vision. This results from rubbing, a foreign object, or a dry/dislodged contact lens. Symptoms include pain, redness, foreign body sensation, and blurriness.
Eye infections like conjunctivitis or keratitis can also cause blurry vision. Conjunctivitis (“pink eye”) is inflammation of the conjunctiva, causing redness, discharge, and mild blurriness. Keratitis, an inflammation of the cornea, is more serious, presenting with pain, light sensitivity, and significant vision reduction.
Acute angle-closure glaucoma is a medical emergency: a sudden, sharp increase in eye pressure causing rapid, severe blurry vision. It often includes intense eye pain, headache, nausea, and halos, requiring immediate treatment to prevent permanent vision loss. Optic neuritis, optic nerve inflammation, can also cause sudden blurry vision or complete vision loss in one eye, often with pain during eye movement, and can be associated with autoimmune diseases.
A sudden blur in one eye could indicate a retinal detachment, where the light-sensitive tissue pulls away from its supporting layers. This often presents with flashes of light, new floaters, or a curtain-like shadow. In rare instances, a transient ischemic attack (TIA) or stroke can affect blood supply to the eye or brain, leading to sudden, painless blurry vision in one eye, sometimes with neurological symptoms like weakness or speech difficulties.
When to Seek Urgent Medical Care
Seek immediate medical attention if blurry vision in one eye is accompanied by sudden, severe pain or complete vision loss. New flashes of light, new floaters, or a dark shadow/“curtain” across your vision are red flags indicating potential retinal detachment, requiring immediate evaluation.
Other concerning symptoms include double vision, a sudden severe headache, or weakness/numbness on one side of the body alongside blurry vision, suggesting a neurological event. If the eye is red, swollen, or discharges, especially with pain or light sensitivity, it may indicate an infection or inflammation needing urgent treatment. Consult an eye care professional if blurriness doesn’t improve quickly or worsens.