Why an Emergency Doctor Must Know — You're on Immunotherapy

Because it changes what your symptom is most likely to mean. Diarrhoea, breathlessness, chest pain or confusion can be an ordinary illness, or an immune-related side effect of immunotherapy that needs different tests and different treatment, usually steroids started quickly. Saying "I am on cancer immunotherapy" in the first minute puts you on the correct pathway immediately.

Checkpoint inhibitor immunotherapy works by activating your immune system against cancer — but the same activation can occasionally attack healthy organs, producing side effects that mimic ordinary illness. NCCN and ASCO guidance on immune-related adverse events (irAEs) exists because these look-alikes need a different response: steroids to calm the immune reaction, not the standard treatment for the illness they resemble.

Without the words "I am on immunotherapy," an emergency doctor has no reason to consider an immune-related cause first — and that is exactly when a treatable reaction gets managed as something ordinary.

This table names what a symptom may turn out to be — it is not a guide to managing any of these at home. Every one of them needs same-day emergency assessment.

Carry information that speaks for you even if you can't. A short alert card or a saved note on your phone, kept somewhere an emergency team will actually look, does most of the work — you don't need anything elaborate, just the right five things.

• Immunotherapy alert card or note — the treatment class ("checkpoint inhibitor immunotherapy"), start date, and treating hospital.
• Your oncology team's direct contact number — so the ER can call your treating doctor directly, any time.
• A one-page treatment summary — cycle number, last dose date, and any past immune reactions you've had.
• A current medicines list, including steroids — especially if you're already on a tapering steroid course.
• Photo ID and insurance or Aarogyasri details — saves time once the emergency itself is under control.

Keep a photo of all five in your phone's gallery, and a printed copy in a wallet or bag — you may not be the one who hands it over.

Say one sentence before anything else: "I am on cancer immunotherapy." This single sentence changes how quickly and how correctly the emergency team responds, because immune-related reactions are tested for and treated differently from the illnesses they resemble.

1. 1

   Say it first

   "I am on cancer immunotherapy" — before describing the symptom itself.

2. 2

   Name the exact symptom and when it started

   Vague descriptions slow down the right tests — be specific about what, and since when.

3. 3

   Hand over your alert card or treatment summary

   Don't wait to be asked — offer it as soon as you're able to speak or a companion can.

4. 4

   Give your oncology team's contact number

   So the ER can coordinate directly with the people who know your case, not guess.

5. 5

   Mention any past immune reactions

   This changes which tests are ordered first and how quickly steroids are considered.

Yes. Checkpoint inhibitor immunotherapy leaves the immune system in an activated state for some time after the last dose, so NCCN and ASCO guidance recognises that immune-related adverse events can appear weeks, and in some cases months, after treatment has technically stopped.

This is why the instruction in this article — tell any treating doctor about a recent course of immunotherapy — does not expire when your last infusion does. If you're between cycles, on a planned break, or have finished treatment altogether, the same alert card and the same first sentence still apply.

Yes, especially whoever is most likely to be with the patient during an emergency. If confusion, fainting or severe illness leaves the patient unable to speak, a spouse or caregiver holding a copy of the same alert card, treatment summary and oncology contact number is often the only way this information reaches the emergency team at all.

A practical habit: keep one copy in the patient's own phone and bag, and a second copy with the family member who usually accompanies them — in a photo, a saved note, or a printed card in their own wallet.

This page covers what to carry and say to any emergency doctor. These related pages cover specific symptoms that need the same urgent response.

• Severe Diarrhoea: The Emergency Most Families Miss — why ongoing diarrhoea on immunotherapy needs same-day assessment, not home management.
• Sudden Breathlessness on Immunotherapy — recognising when new breathlessness is an emergency, not a cold.
• Chest Pain on Immunotherapy: Never Wait — why chest pain or palpitations during immunotherapy should never be waited out.
• Immunotherapy at CION Cancer Clinics — how our tumour board monitors and supports patients through immune-related side effects, from the first infusion onward.

Being Prepared Doesn't Mean Something Will Go Wrong

Patients supported by a tumour board that plans for emergencies in advance report feeling far less anxious about "what if."