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 if nausea or vomiting occurs with:
Chest pain, pressure, severe breathlessness or fainting
A sudden severe headache, confusion, stiff neck or new weakness
Severe or rapidly worsening abdominal pain
Vomit containing blood or material resembling coffee grounds
Suspected poisoning or vomiting after a significant head 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 same-day medical care if you cannot keep fluids down and have signs of dehydration.
These include passing very little urine, dark urine, a very dry mouth, marked dizziness, unusual sleepiness or weakness.
Repeated green vomit, a swollen abdomen, severe pain or being unable to pass stool or gas also needs prompt assessment.
Contact a clinician urgently if you have diabetes and are vomiting, particularly if your blood glucose or ketone levels are high.
Pregnant people should seek prompt advice if vomiting prevents drinking, causes reduced urination or is accompanied by pain or bleeding.
And for anyone, someone who:
has abdominal pain that is severe, constant, or getting worse
is vomiting and cannot keep fluids down
3
Does any of this apply?
Book an appointment
Book a routine appointment if symptoms continue beyond about two days, repeatedly return, cause unplanned weight loss or regularly interfere with eating.
Arrange earlier advice if you have a weakened immune system or a serious long-term condition.
Every sign above is quoted from the sofidex article on Nausea and vomiting – adults. If you are not sure, err upward — it is always reasonable to be checked.