see also:

• ophthalmology

• this is a very common symptom
• the clinician needs to determine if it is monocular or binocular

• ie. double vision with one eye closed
• keratoconus
• astigmatism
• lens subluxation
• structural defects of the eye
• anterior visual cortex defect
• non-organic causes

• strabismus but this usually results in suppression of second image and resultant amblyopia
• fatigue
• voluntary cross-eyed
• medications and substance use
  • alcohol intoxication
  • benzodiazepines or opioids especially if in high doses
  • antoconvulsants
  • ketamine
  • cannabis
  • salicylate poisoning
• concussion
• migraine
• cranial nerve palsy eg. MS, diabetes, brain tumour, intracranial lesions eg. abscess
• orbital myositis
• eye injuries
• dystonic reactions
• myasthenia gravis
• Wernicke's encephalopathy
• Guillain-Barre syndrome (GBS)