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, fainting, sudden heavy or crushing chest pain, blue or grey lips, new one-sided weakness, or a severe allergic reaction.
These symptoms may have causes other than MCTD, but they require immediate 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 urgent medical advice for:
New or rapidly worsening shortness of breath
Chest pain, especially with breathing or activity
Dizziness, fainting, or new ankle swelling
A painful finger or toe that remains blue, pale, or develops a sore
Fever or other signs of infection while taking immune-suppressing medicine
New difficulty swallowing liquids or repeated choking
3
Does any of this apply?
Book an appointment
Arrange routine medical follow-up if your usual symptoms are becoming more frequent, a medicine is causing problems, or daily activities are getting harder.
New reflux, swallowing difficulty, finger sores, joint swelling, muscle weakness, cough, or reduced exercise capacity should also be assessed.
Every sign above is quoted from the sofidex article on Mixed connective tissue disease. If you are not sure, err upward — it is always reasonable to be checked.