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 emergency help after a blow, fall, or collision if you have an enlarged spleen, particularly if abdominal or left shoulder pain develops.
Call emergency services for:
Sudden or severe pain under the left ribs
Pain with dizziness, fainting, weakness, or confusion
Pale, cold, or clammy skin
Rapid breathing or a racing heartbeat after abdominal injury
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 you have known splenomegaly and develop worsening pain, fever, repeated infections, unusual bleeding, easy bruising, or increasing abdominal swelling.
These symptoms can suggest internal bleeding and should not wait for a routine appointment.
3
Does any of this apply?
Book an appointment
Arrange routine medical assessment if you have ongoing discomfort or fullness beneath the left ribs, feel full unusually quickly when eating, or have unexplained fatigue.
These symptoms have many possible causes and do not necessarily mean that your spleen is enlarged.
Every sign above is quoted from the sofidex article on Splenomegaly. If you are not sure, err upward — it is always reasonable to be checked.