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
Call emergency services if you are struggling to breathe, have harsh or noisy breathing, cannot swallow your saliva, or have rapidly increasing neck swelling that affects breathing.
Chest pain, fainting, or severe breathlessness also needs emergency care.
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
Request prompt medical advice if you develop:
Rapid enlargement or sudden pain in the thyroid area
New or persistent hoarseness
Increasing trouble swallowing
Shortness of breath when lying down
Fever with a painful, swollen thyroid
A fast or irregular heartbeat that persists
3
Does any of this apply?
Book an appointment
Arrange a routine appointment if you notice new swelling or a lump at the front of your neck, even if it is painless.
Also seek review if a known goiter appears to be growing or you develop symptoms of an overactive or underactive thyroid.
Every sign above is quoted from the sofidex article on Goiter. If you are not sure, err upward — it is always reasonable to be checked.