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 emergency help for trouble breathing, swelling of the face or throat, fainting, or a widespread blistering rash after using a medicine.
These may indicate a severe reaction rather than vitiligo.
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 urgent medical care for eye pain, marked eye redness, or a sudden change in vision, as these are not typical vitiligo symptoms and need separate assessment.
3
Does any of this apply?
Book an appointment
Arrange a routine appointment if you develop unexplained pale or white patches.
An examination can distinguish vitiligo from infections and other causes of pigment loss.
Routine follow-up is also appropriate if:
Existing patches are spreading quickly or appearing in many new areas
A treatment is irritating your skin or is not helping as expected
Vitiligo is affecting your mood, confidence, work, school, or relationships
You develop possible thyroid symptoms or unexplained changes in health
You want to discuss camouflage, phototherapy, or specialist treatment
The article also says
Vitiligo itself is not an emergency.
Every sign above is quoted from the sofidex article on Vitiligo. If you are not sure, err upward — it is always reasonable to be checked.