What causes double vision?
Double vision may be caused by a variety of underlying conditions or diseases. Some of these conditions, such as cataracts, are fairly common, particularly in older populations, while others may be serious or life threatening in nature. It may appear in only one eye as a result of refractive errors that split or double the image.
More commonly, double vision results from a misalignment of the eyes (strabismus) that prevents both eyes from focusing equally on an object. Misalignment may be present from birth, occur as a result of injury to the brain or the eye area, or be caused by diseases, including multiple sclerosis and diabetes. Alcohol and drugs can also cause temporary double vision.
Common causes of double vision
Double vision may be caused by conditions including:
- Alcohol intoxication
- Cataracts (clouding or loss of transparency in the lens of the eye)
- Diabetes (chronic disease that affects your body’s ability to use sugar for energy)
- Dry eyes
- Misalignment of the eyes
- Multiple sclerosis (disease that affects the brain and spinal cord causing weakness, coordination, balance difficulties, and other problems)
- Refractive error, such as myopia (nearsightedness), hyperopia (farsightedness), or astigmatism (irregularly shaped cornea)
Serious or life-threatening causes of double vision
In some cases, double vision may be a symptom of a serious or life-threatening condition that should be immediately evaluated in an emergency setting. These include:
- Brain or head injury
- Brain tumor
- Injury to the eye
- Optic neuritis (inflammation of the optic nerve)
- Transient ischemic attack (temporary stroke-like symptoms that may be a warning sign of an impending stroke)
Questions for diagnosing the cause of double vision
To diagnose your condition, your doctor or licensed health care practitioner will ask you several questions related to your double vision including:
- When did you first notice your double vision?
- Is the double vision persistent or does it come and go?
- Is the double vision present in one eye or both eyes?
- Are you having any other symptoms associated with your double vision?
- Do you have any other known medical conditions?
- Are you currently taking any medications?
What are the potential complications of double vision?
Double vision is often due to refractive errors or imbalance in the eye muscles; these conditions are not serious and can be treated by corrective lenses or surgery. However, in some cases, double vision may be caused by serious, or even life-threatening, conditions. If you experience double vision, contact your health care provider promptly to determine the underlying condition. Once the underlying cause is diagnosed, it is important for you to follow the treatment plan that you and your health care professional design specifically for you to reduce the risk of potential complications including:
- Brain damage
- Loss of vision and blindness
- Spread of cancer
- Vision problems. Medline Plus, a service of the National Library of Medicine National Institutes of Health. http://www.nlm.nih.gov/medlineplus/ency/article/003029.htm.
- Diplopia (double vision). University of Michigan Kellogg Eye Center. http://www.kellogg.umich.edu/patientcare/conditions/diplopia.html.
- Collins RD. Differential Diagnosis in Primary Care, 5th ed. Philadelphia: Lippincott, Williams & Williams, 2012.
- Kahan S, Miller R, Smith EG (Eds.). In A Page Signs & Symptoms, 2d ed. Philadelphia: Lippincott, Williams & Williams, 2009.
What is double vision?
Double vision, also known as diplopia, occurs when you see objects duplicated in your vision rather than a single clear representation of each object. Double vision may be temporary or permanent. Double vision can be due to a number of different events or conditions ranging in severity from a minor concern to one that is serious or life threatening. The dual images can appear horizontally,... Read more about double visionintroduction
What other symptoms might occur with double vision?
Double vision may accompany other symptoms, which will vary depending on the underlying disease, disorder or condition.Other eye or vision symptoms that may occur along with double vision
Double vision may accompany other symptoms affecting the eye or vision including:
- Abnormal pupils
- Blurred vision
- Droopy eyelids
- Dry eyes Read more about double visionsymptoms