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 a child has:
Severe difficulty breathing or blue or grey lips
Fainting with chest pain, breathlessness, or a racing heartbeat
Severe or persistent chest pain with sweating or marked weakness
Confusion, poor responsiveness, cold mottled skin, or other signs of shock
Cardiac arrest or no normal breathing
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 same-day medical assessment for new chest pain after a recent infection, an unexplained fast or irregular heartbeat, rapidly worsening fatigue, or shortness of breath.
Babies need prompt assessment for rapid breathing, poor feeding, sweating during feeds, unusual sleepiness, or noticeably fewer wet diapers.
For a child already diagnosed with myocarditis, contact the treating team promptly if symptoms return or worsen, swelling develops, weight rises quickly from fluid retention, or medicine cannot be taken because of vomiting.
Routine cardiology follow-up is different from urgent care.
3
Does any of this apply?
Book an appointment
Keep planned appointments even when the child feels well, because heart function and rhythm can change without obvious symptoms.
Every sign above is quoted from the sofidex article on Myocarditis - pediatric. If you are not sure, err upward — it is always reasonable to be checked.