When to Call Your Oncology Team

Fever, Chills and Infection

Fever is the single most important symptom in cancer treatment, because chemotherapy suppresses the neutrophils that normally contain a bacterial infection. When neutrophil counts are low, an infection that would normally take days to become serious can become life-threatening in hours, and the usual signs of infection — pus, redness, swelling — may be absent because there are no white cells to produce them. Fever may be the only clue.

The Threshold

• 100.4°F / 38.0°C once — emergency department, now.
• 100.0°F / 37.8°C or above, twice, an hour apart — same.
• Chills or rigors with a normal temperature — still an emergency. Bacteria entering the bloodstream commonly cause rigors before the temperature rises, and paracetamol or acetaminophen taken for another reason can mask the fever entirely.

Infection Signs Without Fever

Report these the same day even with a normal temperature: burning or stinging on passing urine, a new productive cough, a sore throat that makes swallowing painful, redness or tenderness around a central line or port, a new area of hot red skin anywhere, or perianal pain. In a neutropenic patient any of these can be the entry point for bloodstream infection.

Why Your Bloods Can Look Normal

Patients are often confused when they are admitted with a fever and told their white count is normal. Two things explain this. The counts drop to their lowest around day 7 to 14 after chemotherapy, so a fever on day 3 may arrive before the nadir. And a stress response can push immature white cells out of the marrow, keeping the total count up while the functional neutrophil count is low. A normal white count never rules out serious infection during chemotherapy, and it does not mean you were wrong to come in.

Diarrhoea, Vomiting and Dark Stools

Diarrhoea

Grading is based on how many extra stools you are having compared with your normal pattern.

• 1–3 extra stools a day, otherwise well: Start the anti-diarrhoeal your team gave you, keep drinking, and report it at your next contact.
• 4–6 extra stools a day, or any night-time diarrhoea: Call the same day. Dose adjustment or an alternative anti-diarrhoeal is often needed.
• 7 or more extra stools a day, diarrhoea with fever, blood in the stool, dizziness on standing, or inability to drink: Emergency department. Dehydration and electrolyte loss are what cause harm here, and both are fixable with intravenous fluids.

Certain drugs carry specific instructions. Irinotecan can cause an early cholinergic diarrhoea during or just after the infusion, treated with atropine, and a delayed diarrhoea days later treated with high-dose loperamide on a strict schedule. 5-FU and capecitabine diarrhoea can be dose-limiting and sometimes signals DPD deficiency. Follow the written instructions your unit gave you for your specific regimen. Our diarrhoea management guide covers this in more detail.

Nausea and Vomiting

Call the same day if you have vomited more than twice in 24 hours, cannot keep tablets down, or cannot keep fluids down for 12 hours. Anti-sickness medication that is not working is a reason to call rather than to endure — there are several classes and switching usually helps. See managing nausea and vomiting.

Black or Dark Stools

Black, tarry, foul-smelling stool suggests bleeding higher in the digestive tract and is an emergency, particularly if platelets are low or you are on an anticoagulant. Two harmless mimics are worth knowing: oral iron tablets turn stool a dark greenish-black, and bismuth preparations such as Pepto-Bismol turn it black. If you are taking neither, treat dark stool as bleeding until proven otherwise and go in. Bright red blood also needs reporting the same day.

Immunotherapy: Different Rules

Checkpoint inhibitors such as pembrolizumab, nivolumab and atezolizumab do not suppress the bone marrow, so the classic neutropenic fever rule matters less. The risk is the opposite: an over-activated immune system attacking healthy organs. These immune-related adverse events can appear weeks or even months after a dose, including after treatment has stopped, and they escalate quickly once they begin.

Report any of these promptly, and always mention that you are on immunotherapy — a clinician who does not know this may treat the symptom rather than the cause:

• Diarrhoea of any grade — the threshold is lower than for chemotherapy, because immune colitis can perforate the bowel. New diarrhoea on a checkpoint inhibitor is reported the same day, not managed with loperamide alone.
• Dark stools or blood — may indicate immune colitis with bleeding. Urgent.
• New shortness of breath or a dry cough — possible pneumonitis, which needs prompt steroids.
• Yellowing of the eyes or skin, or dark urine — possible hepatitis.
• Profound fatigue, dizziness, unexplained weight change, feeling cold all the time — thyroid, adrenal or pituitary involvement. Adrenal insufficiency can be life-threatening and is easily missed as "just tiredness".
• Excessive thirst and passing large volumes of urine — new-onset diabetes can develop abruptly.
• A rash that blisters, peels, or covers a large area, or any rash with mouth sores.

See our immunotherapy guide for how these are graded and treated.

Breathing, Chest and Circulation

• Emergency: Sudden breathlessness, chest pain or tightness, coughing blood, a fast or irregular heartbeat with dizziness, fainting, or one leg becoming swollen, warm and painful. Cancer and several of its treatments raise clotting risk substantially, and pulmonary embolism and deep vein thrombosis are common enough that they should be the first thought, not the last.
• Same day: Breathlessness that has crept up over days, a new persistent dry cough, or ankle swelling. Anaemia, pleural effusion, pneumonitis and cardiac effects of anthracyclines and trastuzumab all present this way.
• Next appointment: Mild breathlessness only on strenuous exertion, unchanged over weeks, with no chest pain.

Neurological and Neuropathy Symptoms

• Emergency: Sudden severe headache, confusion, new weakness or numbness on one side, difficulty speaking, visual loss, a seizure, or new back pain with leg weakness, numbness in the saddle area, or loss of bladder or bowel control. That last combination can indicate spinal cord compression, where hours of delay determine whether walking is preserved.
• Same day: New tingling or numbness that has spread from the fingertips or toes toward the hands and feet, or that is making it hard to fasten buttons, hold a cup, or feel the floor when walking. Platinum agents and taxanes cause peripheral neuropathy that can become permanent if dosing is not adjusted in time. Reporting early is what preserves function.
• Next appointment: Mild, stable pins and needles in the fingertips that is not interfering with daily tasks — still worth documenting at every visit so the trend is visible.

Skin, Mouth and Infusion Site

• Emergency: Pain, burning, swelling or leaking at the infusion site during or shortly after a treatment — a possible extravasation, where the drug has leaked into surrounding tissue. Say something during the infusion; do not wait to be polite. Also emergency: a rapidly spreading rash, blistering, peeling skin, or facial and tongue swelling.
• Same day: Redness, tenderness or discharge around a port or central line. Mouth sores that stop you eating or drinking, or that look white and coated. Radiotherapy skin that has broken down, is weeping, or has become newly painful and hot — see radiation dermatitis by grade.
• Next appointment: Mild dryness, itching or pinkness in a radiotherapy field, or a few small mouth ulcers you can eat around. Our mouth sores guide covers home care.

Quick Triage Table

Where this table and the instructions from your own treating team differ, follow your team. They know your regimen, your counts and your comorbidities.

How to Make the Call Count

Every oncology unit provides a 24-hour contact number, usually printed on an alert card issued at the start of treatment. Save it in your phone before you need it, and keep the card in your wallet — it tells any hospital you attend that you are on chemotherapy, which regimen, and who to contact.

Have These Ready Before You Dial

• Your temperature, taken now, and the reading device used
• The name of your regimen and the date of your last treatment
• The day number since that treatment — day 8 and day 20 mean very different things
• What the symptom is, when it started, and whether it is getting worse
• Anything you have already taken for it, including paracetamol and loperamide
• Your current medicines, allergies, and hospital or MRN number

Common Reasons People Wait Too Long

• "It's the middle of the night." The line is staffed for exactly this. Neutropenic sepsis does not improve by morning.
• "I don't want to make a fuss." Units would far rather assess ten people who turn out to be fine than admit one person six hours late.
• "I feel completely well apart from the temperature." Feeling well is normal in the early hours of neutropenic sepsis. The fever is the warning; deterioration comes afterwards.
• "I have an appointment in two days anyway." Fever, chills, breathlessness and bleeding do not wait for appointments.

For Family Members and Carers

Practical help matters most in the first hour. Take the temperature and write down the reading and the time. Find the alert card. Drive rather than waiting for an ambulance if the person is stable enough and the hospital is close. At triage, say the words "on chemotherapy, fever" first. Bring the current medicines list. Afterwards, watch for the pattern that a second fever after a first course of antibiotics is common and needs the same urgent response as the first — it is not a sign that going in was pointless.

Frequently Asked Questions

What temperature is an emergency during chemotherapy?

A single reading of 100.4°F (38.0°C), or 100.0°F (37.8°C) on two readings an hour apart. Different centres phrase it slightly differently, but every one of them treats a temperature of 38°C as a reason to be assessed immediately rather than observed at home.

I have chills and shivering but my temperature is normal. Do I still call?

Yes, and treat it as urgent. Rigors frequently precede the temperature rise when bacteria enter the bloodstream. This is one of the situations where waiting to "confirm" a fever loses the hours that matter most.

Which infection symptoms need urgent care during chemotherapy?

Fever, rigors, breathlessness, confusion and low blood pressure need emergency assessment. Burning on urination, a productive cough, a painful sore throat, redness around a line, and new hot red skin need a same-day call, because in a neutropenic patient any of these can progress to bloodstream infection quickly.

How many days after chemotherapy is infection risk highest?

Roughly days 7 to 14 after each dose, when the neutrophil count reaches its nadir, with recovery usually by days 21 to 28. That is when vigilance should be highest — but fever at any point in the cycle is still treated as an emergency, and it is not safe to relax after day 14.

Should I go to my regular ER or a cancer centre?

Go to the nearest emergency department if you are unwell — time to antibiotics matters more than which hospital gives them. If your cancer centre runs a direct-access acute oncology unit and you are stable, ring the 24-hour line first; they will often bring you straight in and bypass the general queue.

What if I called last week about something similar?

Call again. Recurrence of a symptom that was previously assessed does not make it less significant, and a second fever during the same cycle is a specific reason to be seen rather than reassured.

Related Resources