When should you see a doctor about blurred vision?

Blurred vision can result from dry eye, an uncorrected focusing problem, migraine, or changes in blood glucose. Hypertension and type 2 diabetes can affect the eyes and need medical monitoring. A change in vision does not identify one diagnosis, so the timing, one-eye or two-eye pattern, and associated symptoms are useful details.

Stop driving or operating machinery while vision is unclear. Remove contact lenses if the eye is irritated and avoid rubbing it. Note when the blurring began, whether it fluctuates, and any pain, flashes, floaters, headache, weakness, or speech change. Do not use someone else's eye drops.

Seek emergency help for sudden loss or major change of vision, a curtain-like shadow, severe eye pain, a red painful eye, new weakness or numbness, facial drooping, trouble speaking, or a severe sudden headache. Arrange prompt assessment for new persistent blurring, repeated episodes, or vision changes in someone with diabetes or high blood pressure.

Ask whether you need an eye examination, blood pressure or glucose checks, medication review, or urgent specialist assessment, and which changes should trigger immediate help.