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
Elsewhere, use your local poison information service or emergency number.
Call emergency services now if the person has:
Trouble breathing, noisy breathing, or increasing throat swelling
Collapse, severe drowsiness, confusion, or a seizure
Inability to swallow, heavy drooling, or persistent vomiting
Severe chest or abdominal pain
Blood in vomit or black, tar-like stool
A large or concentrated ingestion
Severe eye pain or sudden loss of vision
And for anyone, someone who:
you believe has taken an overdose or swallowed something poisonous
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
2
Is any of this happening?
Be seen today
Contact a poison centre immediately after trisodium phosphate is swallowed, even if there are no symptoms yet.
In the United States, Poison Control is available at 1-800-222-1222.
Do not wait for a routine appointment in these situations.
Prompt medical advice is also needed for ongoing eye pain after rinsing, a worsening skin burn, cough or breathlessness after inhalation, or any exposure involving a young child.
3
Does any of this apply?
Book an appointment
After the immediate recovery period, arrange routine follow-up for new or worsening difficulty swallowing, repeated regurgitation, food sticking, poor intake, or unexplained weight loss.
These can be signs of scar-related narrowing.
Every sign above is quoted from the sofidex article on Trisodium phosphate poisoning. If you are not sure, err upward — it is always reasonable to be checked.