Go through these in order and stop at the first one that applies. If you are reading this for someone else, answer for them.
1
Is any of this happening now?
Call 911
Get urgent or emergency eye care for:
Sudden loss or major reduction of vision
Severe eye pain
A chemical splash or penetrating injury
New flashes, many floaters, or a curtain-like shadow
Marked light sensitivity with headache, nausea, or vomiting
These symptoms are not usual features of a pterygium and may have another cause that needs rapid assessment.
Other emergency signs, for anyone
Someone who is struggling to breathe, gasping, choking, or cannot get words out
Someone who has chest pain, tightness or pressure lasting more than a few minutes
Someone who has sudden weakness or drooping on one side of the face or body, slurred speech, or sudden confusion
Someone who is unconscious, or cannot be woken
Someone who is bleeding heavily and it will not stop with firm pressure
Someone who has had a seizure that will not stop, or does not wake up afterwards
Someone who has lips or skin that look pale, blue, grey or blotchy
Someone who you believe has taken an overdose or swallowed something poisonous
2
Is any of this happening?
Be seen today
Seek prompt assessment if the growth changes quickly, develops an unusual colour or shape, bleeds without injury, or causes increasing pain.
These features do not prove that something serious is present, but they are not typical of a quiet, stable pterygium.
3
Does any of this apply?
Book an appointment
Arrange a routine eye examination if you notice a new growth on the eye, ongoing redness, repeated irritation, or gradual changes in vision.
You should also arrange review if a known pterygium appears to be growing, affects contact lens wear, or no longer responds to your usual comfort measures.
Every sign above is quoted from the sofidex article on Pterygium. If you are not sure, err upward — it is always reasonable to be checked.