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
Pinworms do not normally require emergency treatment.
Seek emergency help for severe abdominal pain with collapse, marked confusion, or difficulty waking.
These are not expected pinworm symptoms.
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 care for spreading redness, swelling, pus, fever, painful urination, or worsening abdominal or pelvic pain.
These symptoms are not typical of a simple pinworm infection and may have another cause.
3
Does any of this apply?
Book an appointment
Arrange routine medical advice if:
Symptoms continue after the full treatment course and hygiene measures
Infections repeatedly return
The skin around the anus is persistently sore
There is vulvar or vaginal itching or discharge
Treatment is being considered during pregnancy or breastfeeding
The affected child is younger than 2 years
The article also says
A pharmacist or primary care clinician can help if pinworms are suspected, particularly when no worm has been seen or the correct treatment is uncertain.
Every sign above is quoted from the sofidex article on Pinworms. If you are not sure, err upward — it is always reasonable to be checked.