Side Effect: Double Vision (Diplopia)

Double vision, also known as diplopia, is a vision disorder in which a person perceives two images of a single object instead of one.

• Double vision can appear as two images that are slightly off-center, or as two images that are widely separated.
• The images may be horizontal, vertical, or diagonal to one another.
• In some cases, double vision may only occur when looking in a particular direction.
• Some people may also experience dizziness, nausea, and difficulty focusing or tracking moving objects.

• Double vision can be caused by brain injury, nerve damage, muscle weakness, eye disorders, or a medication side effect.
• Patients with cancer can develop double vision due to:
  • brain tumors or metastases
  • direct effect of a tumor on the eye muscles
  • as a side effect of certain cancer treatments

Preventing double vision involves monitoring for signs and symptoms of eye muscle weakness and promptly treating underlying conditions.

In some cases, regular eye exams may also be recommended to help detect any changes in vision in order to prevent small problems from becoming bigger ones.

Treatment options for double vision in patients with cancer depend upon the underlying cause. In some cases, the cancer itself may need to be treated to alleviate the symptoms of double vision.

Supportive measures may include:

• medicated and non-medicated eye drops
• corrective lenses
• eye patches
• prism glasses
• surgery

If symptoms are medication related, the offending agent may have to be adjusted or discontinued. Prompt diagnosis and treatment of the underlying cause of double vision can help prevent complications and improve quality of life.