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 you have:
Trouble breathing, wheezing, or swelling of the face, tongue, or throat
Fainting, severe confusion, a seizure, or difficulty staying awake
Severe or spreading muscle cramps, chest pain, or abdominal rigidity
Heavy sweating, drooling, repeated vomiting, or muscle twitching
A suspected Australian funnel-web bite
Rapid deterioration after any suspected bite
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 urgent medical assessment for dark urine, yellow skin or eyes, unusual paleness, severe weakness, or reduced urination.
These can be signs of red blood cell breakdown or kidney injury.
Prompt medical advice is also appropriate for a suspected widow or recluse bite, severe pain, an enlarging blister or open sore, fever, pus, or redness spreading away from the wound.
Children, older adults, pregnant people, and those with significant health conditions may need earlier assessment.
And for anyone, someone who:
has a wound that is hot, spreading red, or leaking pus
3
Does any of this apply?
Book an appointment
For routine follow-up, arrange a review if the wound is not steadily improving, keeps reopening, or needs ongoing dressing care.
A poison information service can provide location-specific advice about dangerous spiders and first aid.
Every sign above is quoted from the sofidex article on Spider bites. If you are not sure, err upward — it is always reasonable to be checked.