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 for severe breathing difficulty, inability to speak in full sentences, new confusion, extreme drowsiness, fainting, severe chest pain, or blue-grey lips or skin.
These signs can mean that oxygen is dangerously low or another serious problem is present.
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
If you already have COPD, seek prompt medical advice when symptoms are clearly worse than usual, particularly if:
Your reliever inhaler is helping less or is needed more often
Breathlessness, coughing or wheezing is increasing
Phlegm becomes much thicker, more plentiful or changes colour
You develop a fever or signs of a chest infection
You are struggling to eat, drink, sleep or manage normal activities
3
Does any of this apply?
Book an appointment
Arrange a routine appointment if you have a persistent cough, regular phlegm or breathlessness that limits activity, especially if you smoke or have had long-term exposure to dust or fumes.
The article also says
Use your agreed flare-up plan if you have one.
Do not delay getting advice because you have treatment at home.
Every sign above is quoted from the sofidex article on COPD. If you are not sure, err upward — it is always reasonable to be checked.