Recognising an emergency during your child's treatment

A single temperature of 38°C or above is generally considered a potential fever emergency when a child is receiving chemotherapy — even if your child looks reasonably well at that moment. Children on chemotherapy can have dangerously low white blood cell counts (neutropenia), which means their body cannot fight infection in the normal way. A fever is often the only early sign of a serious infection. Do not wait to see if the temperature comes down. Do not give paracetamol and wait an hour. Call your oncology team or go directly to the emergency department immediately. Tell them your child is on chemotherapy — this will ensure they are triaged as urgent. Your oncology team will have given you a specific fever protocol; follow that protocol even if the fever seems mild.

A nosebleed that does not stop after 10 to 15 minutes of steady pressure should be evaluated the same day — call your oncology team straight away. Children on chemotherapy often have low platelet counts (thrombocytopenia), which means their blood cannot clot normally. A prolonged nosebleed is one of the signs of low platelets. Other signs that suggest low platelets include: small red or purple dots on the skin (petechiae), unusual bruising, bleeding gums, blood in the urine, or dark tarry stools. If you see any of these alongside a nosebleed, or if the bleed is heavy, go directly to the emergency department without waiting to call the team first.

For children receiving cancer treatment, ibuprofen and aspirin are generally not recommended because they can affect platelet function and may mask important signs of infection. Paracetamol is generally considered safer, but many oncology teams advise against giving any fever-lowering medicine before calling them first — because the fever itself is a key signal they need to assess. Giving a fever-reducer before calling the team can lower the temperature and make the situation appear less serious than it is, delaying treatment for what could be febrile neutropenia. Your child's oncology team will have specific instructions for your child's situation. Follow those instructions, and when in doubt — call before you give anything.

Allergic reactions to treatment can range from mild skin reactions to a severe whole-body response called anaphylaxis. Signs to watch for during or shortly after an infusion include: hives or itching, swelling of the face, lips or throat, sudden difficulty breathing, a tight feeling in the chest, a very fast heartbeat, dizziness or feeling faint, and vomiting. If your child is receiving an infusion in a clinic, trained staff are present to manage reactions — tell them immediately if your child reports any unusual feeling. If you notice these signs at home (for example after an oral medicine or a short time after leaving the clinic), call emergency services and the oncology team at the same time. Do not wait to see if the reaction passes.

Call emergency services or go directly to the nearest hospital emergency department — without calling the oncology team first — if your child: is unconscious or very difficult to rouse; has a seizure; cannot breathe or is breathing with great difficulty; has severe chest pain; has collapsed; or is having a severe allergic reaction with throat swelling or inability to breathe. In any of these situations, every minute matters and the first step is calling emergency services. You can call the oncology team from the ambulance or emergency department. For all other concerns — fever, unusual bleeding, persistent vomiting, pain — call your oncology team first and they will tell you whether to come in. Keep both numbers saved in your phone.

Some nausea and vomiting is common during chemotherapy and is managed with anti-sickness medicines. It becomes a concern that warrants calling your oncology team when: vomiting is severe enough that your child cannot keep down any fluids for more than six hours; your child is showing signs of dehydration (dry lips, very little urine, sunken eyes, extreme tiredness); the vomiting brings up blood or what looks like coffee grounds; or if your child is also running a fever at the same time. Children can become dehydrated quickly, and dehydration during treatment makes other side effects harder to manage. If you are unsure, call the oncology team — they would always prefer a cautious call to finding out later that your child needed help earlier.