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
Get urgent or emergency help if:
You cannot breathe normally or feel that your throat is closing
You are choking or cannot swallow saliva
A severe spasm causes an injury
New stiffness occurs with fever, confusion, heavy sweating, or reduced awareness
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 prompt medical advice if symptoms are worsening quickly, causing significant pain, interfering with walking or eating, or leading to falls.
New swallowing problems should also be assessed promptly.
3
Does any of this apply?
Book an appointment
Arrange a routine appointment if you notice new twisting movements, repeated muscle pulling, unusual postures, or persistent stiffness while taking or after stopping a dopamine-blocking medicine.
Bring a complete medicine list, including medicines taken for nausea and medicines used in the past.
The article also says
Fever, marked rigidity, and confusion after a medicine change can indicate a different serious medication reaction rather than tardive dystonia.
Every sign above is quoted from the sofidex article on Tardive dystonia. If you are not sure, err upward — it is always reasonable to be checked.