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 now if drooling occurs with:
Severe trouble breathing, choking, or blue or grey lips
Inability to swallow saliva
Sudden facial drooping, arm weakness, or difficulty speaking
Rapid swelling of the tongue, lips, or throat
Suspected poisoning or swallowing of a dangerous substance
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 same-day medical care for new drooling with fever, marked throat pain, a stiff or swollen neck, a muffled voice, dehydration, or worsening trouble swallowing.
A child who is drooling, looks unwell, and refuses to swallow also needs prompt assessment.
3
Does any of this apply?
Book an appointment
Book a routine appointment if drooling is persistent, newly increasing, damaging the skin, disrupting sleep, or affecting eating, speech, school, work, or social activities.
Arrange an assessment if you regularly cough or choke during meals, lose weight without trying, or develop repeated chest infections.
The article also says
Do not force food or drink if swallowing is difficult.
If an object may be stuck in the throat, do not sweep inside the mouth with your fingers unless you can clearly see and safely remove it.
Every sign above is quoted from the sofidex article on Drooling. If you are not sure, err upward — it is always reasonable to be checked.