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, contact your local poison centre or emergency service.
Call emergency services now for:
Trouble breathing, collapse, seizure, severe confusion, or inability to wake
Vomiting blood, severe or worsening abdominal pain, or repeated vomiting
Signs of shock, such as fainting, cold skin, or extreme weakness
Very little urine after significant vomiting or suspected poisoning
A swallowed button battery or battery of unknown type
Exposure to a zinc-containing pesticide or unknown industrial chemical
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 if you or someone else may have swallowed more zinc than intended, even if symptoms have not started.
In the United States, Poison Control is available at 1-800-222-1222.
Breathing difficulty or chest pain requires urgent care.
3
Does any of this apply?
Book an appointment
Arrange a non-emergency medical appointment if you have been taking several zinc products for weeks or months, or if you develop ongoing fatigue, frequent infections, numbness, poor balance, weakness, or difficulty walking.
The article also says
Work-related fever, cough, or muscle aches after welding or metal cutting should be reported and medically assessed, especially if episodes recur.
Every sign above is quoted from the sofidex article on Zinc poisoning. If you are not sure, err upward — it is always reasonable to be checked.