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
Seek emergency help for:
Severe difficulty breathing, blue or grey lips, or rapidly worsening breathlessness
New confusion, extreme drowsiness, fainting, or difficulty waking
A seizure, sudden weakness, or a severe headache with a stiff neck
Sudden loss of vision
Signs of shock, such as cold clammy skin with marked weakness
Symptoms that are worsening quickly over minutes or hours
Do not wait for a routine appointment if you develop the urgent or emergency symptoms above.
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
Fever or infection symptoms may require same-day assessment even when you do not feel very unwell.
Get prompt medical advice for a new or persistent fever, worsening cough, mouth sores, painful swallowing, diarrhea, weight loss, rash, unusual headache, or vision change.
This is especially important during chemotherapy, after a transplant, with a very low CD4 count, or while taking strong immune-suppressing medicines.
And for anyone, someone who:
has a fever with a stiff neck, a rash that does not fade under pressure, or severe headache
has a wound that is hot, spreading red, or leaking pus
3
Does any of this apply?
Book an appointment
Routine follow-up is appropriate when symptoms are stable and you are attending planned reviews.
The article also says
If you have severe immune suppression, follow any written instructions from your treatment team.
Every sign above is quoted from the sofidex article on Opportunistic infections. If you are not sure, err upward — it is always reasonable to be checked.