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 an exposed person has:
Trouble breathing, blue or grey lips, or severe chest tightness
Collapse, inability to wake, severe confusion, or a seizure
Choking or repeated coughing after swallowing the solvent
Severe weakness, poor coordination, or an abnormal heartbeat
Exposure inside an enclosed space followed by significant symptoms
Elsewhere, use your local poison centre or emergency advice service.
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 information service promptly after swallowing Stoddard solvent, even if there are no symptoms yet.
In the United States, Poison Control can be reached at 1-800-222-1222.
Seek urgent medical assessment for increasing cough, fever, chest pain, rapid breathing, wheezing, vomiting, or unusual drowsiness after exposure.
3
Does any of this apply?
Book an appointment
Arrange routine medical follow-up for skin irritation that does not settle, recurring symptoms at work, or ongoing headaches, concentration problems, cough, or breathlessness.
Workplace exposures can also be reviewed by an occupational health service.
The article also says
Do not enter a contaminated enclosed area to attempt a rescue unless you have appropriate training and protective equipment.
Every sign above is quoted from the sofidex article on Stoddard solvent poisoning. If you are not sure, err upward — it is always reasonable to be checked.