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 if swelling makes it difficult to breathe or swallow, spreads toward the eye or neck, or becomes extensive very quickly.
These signs can mean an infection is affecting deeper tissues.
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
Book sooner if a tooth feels loose or the swelling is painful.
Seek urgent, same-day dental or medical care if you have:
Increasing gum, tooth, facial, or jaw swelling
Fever or a general feeling of being unwell
Severe or rapidly worsening pain
Pus or a bad taste together with pain and swelling
Difficulty opening your mouth
And for anyone, someone who:
has a wound that is hot, spreading red, or leaking pus
3
Does any of this apply?
Book an appointment
Arrange a routine dental appointment if the swelling lasts more than several days, keeps returning, or comes with repeated bleeding, persistent bad breath, receding gums, or changes in how your teeth fit together.
Every sign above is quoted from the sofidex article on Swollen gums. If you are not sure, err upward — it is always reasonable to be checked.