There is no single examination timetable that suits everyone. Age, symptoms, family history, general health and previous findings all influence how often the eyes should be assessed.
Do not wait for obvious blur
Some eye conditions can develop before a person notices a change. Diabetes, a strong family history of glaucoma, high short-sightedness and certain medicines may justify individual monitoring advice.
Everyday clues
Frequent squinting, headaches during close work, difficulty with night driving, closing one eye or holding material unusually near or far are reasons to arrange a check. Children may not describe blur clearly, so behaviour matters.
Urgent is different from routine
Sudden vision loss, injury, chemical exposure, severe pain, new double vision, flashes or a shadow in vision require urgent guidance. Contact an emergency service or appropriate eye-care provider rather than waiting for a routine appointment.
A clear next step
Write down what you have noticed, when it began and which activities are affected. That simple record can make a professional conversation more focused and useful.