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 or go to an emergency department for difficulty breathing or swallowing, rapidly spreading swelling of the face or neck, or swelling affecting the eye.
These symptoms require emergency 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 same-day dental or medical advice for:
Increasing facial or gum swelling
Fever or feeling generally unwell with dental swelling
Severe or worsening pain that is not controlled as advised
Pus, a bad taste, or new drainage around the tooth
3
Does any of this apply?
Book an appointment
Contact the dental team during office hours if tenderness is not improving, your bite feels uneven, or a temporary filling or crown becomes loose or falls out.
These concerns usually need prompt dental review but are not emergencies.
Every sign above is quoted from the sofidex article on Root canal. If you are not sure, err upward — it is always reasonable to be checked.