Symptom

Double vision

Sudden double vision needs urgent care

Clinically reviewed · Last reviewed 2026-06-13

When to get urgent help

  • Sudden onset of double vision
  • Double vision with a headache, droopy eyelid or pupil change
  • Double vision with weakness, numbness or slurred speech
  • Double vision after a head or eye injury

Common causes

Double vision can be in one eye or both. These are common causes, with the conditions to read next.

Squint (strabismus) Misaligned eyes are a common cause, especially if long-standing. Thyroid eye disease Bulging or restrictive eye muscles from thyroid disease can cause double vision. Droopy eyelid (ptosis) A drooping eyelid can occasionally contribute to vision imbalance. Cataracts Clouding can sometimes cause ghosting or doubling in one eye. Astigmatism An uncorrected focusing error can cause shadowing in one eye.

What can help

  • Note whether the doubling is in one eye or both, which helps diagnosis
  • Have an eye test for long-standing or gradual double vision
  • Treat sudden double vision as urgent rather than waiting

Frequently asked questions

Is double vision serious?

New or sudden double vision, especially with a headache, droopy eyelid, weakness or speech changes, needs urgent assessment. Long-standing double vision should still be checked.

What causes double vision?

It can come from the eyes not aligning, such as a squint, or from focusing problems and other conditions. Whether it affects one or both eyes helps find the cause.

Can glasses fix double vision?

Some causes, such as uncorrected focusing errors, improve with glasses, and special prism lenses can help certain squints. The right treatment depends on the cause.

Can double vision be a sign of stroke?

Sudden double vision with weakness, numbness, slurred speech or a severe headache can signal a stroke or TIA and needs emergency care. Long-standing double vision still needs assessment but is less likely to be a stroke.