The most noticeable sign of anisocoria is one pupil being larger than the other. In some cases, this is the only symptom present, while in advanced cases, it can cause blurred vision, double vision, or sudden vision loss. Symptoms of anisocoria may include:

Eye pain
Blurred vision
Double vision (diplopia)
Light sensitivity (photophobia)
Sudden vision loss
Headache
Fever
Nausea or vomiting
Neck pain or stiffness