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 the exposed person has:
Trouble breathing, severe wheezing, or blue or grey lips
Persistent coughing or choking after swallowing the liquid
Severe confusion, unusual drowsiness, or difficulty waking
A seizure, collapse, or loss of consciousness
Exposure to concentrated vapor in an enclosed space with significant symptoms
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 promptly after mineral spirits have been swallowed, even if there are no symptoms yet.
In the United States, Poison Control is available at 1-800-222-1222 .
Elsewhere, use the local poison information service.
3
Does any of this apply?
Book an appointment
Arrange non-emergency medical follow-up for a cough that does not settle, continuing shortness of breath, a persistent skin rash, or repeated headaches and dizziness linked to solvent use.
The article also says
Move someone exposed to vapor into fresh air only if this can be done safely.
Do not enter a contaminated enclosed space without proper protective equipment.
Do not give food or drink to someone who is very drowsy, vomiting repeatedly, or having difficulty swallowing.
Every sign above is quoted from the sofidex article on Mineral spirits poisoning. If you are not sure, err upward — it is always reasonable to be checked.