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Diplopia: The Reason for Double Vision

Double vision is both serious and unpleasant. Find out more about it here.

Diplopia is commonly referred to as double vision. This is a serious condition that affects the eyes’ ability to produce a single image in your brain. The two forms of diplopia are binocular and monocular double vision.

Causes of double vision

What causes double vision? There are many things that may cause diplopia, especially short term or temporary diplopia. For instance, the must common reasons for temporary double vision are alcohol intoxication, concussion and fatigue.

Some medications may cause diplopia as a side effect, such as hypnotics and anti-epileptics. Always seek medical attention immediately if you experience double vision symptoms.

What causes binocular double vision?

Binocular double vision is the most common type of diplopia. To tell if you have binocular vision simply do this: if you close one eye and the problem persists, then you have monocular double vision in that eye. One common cause is strabismus, or, lazy eye.

This happens when the extra ocular muscles that hold the eyeball become weak or paralysed, meaning that both eyes cannot focus on the same point at the same time. Strabismus can be treated or reduced if caught early in children.

However, the actual cause of binocular double vision is incredibly hard to diagnose properly since there are hundreds of potential factors.

The condition either starts from the eye itself, to the optic nerves in the brain. Some cases of double vision are benign, and some are very dangerous. In fact, the task is so hard that the Professor of Ophthalmology at Harvard called it “intimidating”.


One treatment for double vision is prism lenses in your glasses.

What causes monocular double vision?

Monocular double vision is rare compared to binocular diplopia. It is caused by an astigmatism, which is when the cornea is shaped irregularly causing it to refract light abnormally. Cataracts or even dry eyes can also cause monocular double vision.

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