When to call your care team

A simple guide to which symptoms need 911, which need a call to your care team right away, and which can wait for office hours.

Rosa: Hi, I'm Rosa. It can be hard to know when a symptom is serious. Let's go over when to call 911, when to call your care team right away, and when it can wait for office hours.

During cancer treatment, some problems can get serious fast. Knowing when to call, and who to call, can keep you safe. This page sorts warning signs into three groups: call 911, call your care team right away, and call during office hours.

Your care team wants to hear from you. You are never a bother when you call about a symptom. It is always better to call and learn it is minor than to wait too long.

Keep your clinic's after-hours number handy. Most cancer clinics have a doctor or nurse on call at night, on weekends, and on holidays. Save the number in your phone and post it on your fridge. Make sure your family knows where to find it.

Never wait until morning with a fever during chemotherapy. A fever can be the first sign of a serious infection. Do not take fever medicine before you call, unless your team told you to.

When you call, have this ready: your name and date of birth, your type of cancer and treatment, the date of your last treatment, your symptoms and when they started, and your temperature if you checked it. If you cannot reach anyone and you feel worse, go to the emergency room. Tell them you are getting cancer treatment.

Your team may give you other warning signs that fit your treatment. Follow their advice first.

Call 911

Call 911 or go to the nearest emergency room for the signs below. Do not drive yourself.

Trouble breathing or chest pain

Call 911 if you cannot catch your breath, or if you have pain, pressure, or tightness in your chest.

Signs of a stroke

Call 911 for a drooping face, sudden weakness or numbness on one side of the body, trouble speaking, trouble seeing, or a sudden very bad headache.

Fainting, seizure, or severe bleeding

Call 911 if you pass out, have a seizure, or have bleeding that will not stop after pressing on it firmly.

Call your care team right away, day or night

Call for any of the signs below, even at night, on a weekend, or on a holiday. If you cannot reach anyone, go to the emergency room.

Fever or chills

A temperature of 100.4°F (38°C) or higher, or chills, during treatment. Shaking chills, even without a fever.

Vomiting, diarrhea, or not drinking

Vomiting or diarrhea that will not stop, or you cannot keep fluids down. Not peeing, or peeing much less than usual.

New pain, bleeding, or bruising

New, severe pain. New bleeding, such as blood in your pee or stool, black stools, or a nosebleed that will not stop. Bruises you cannot explain.

Breathing changes on immunotherapy

New shortness of breath or a new cough. Immunotherapy can sometimes cause swelling in the lungs, which needs care quickly.

Swelling or pain in one leg

This can be a sign of a blood clot. If you also have chest pain or trouble breathing, call 911.

Confusion

New confusion, acting not like yourself, or being much sleepier than usual. A family member may notice this first. If the person is very hard to wake, call 911.

Call during office hours

Call during the day for milder symptoms or ones that change slowly, such as mild nausea, constipation, feeling tired, a small rash, or a sore mouth that still lets you eat and drink. Also call for refills, appointment changes, and questions.

If you are not sure

Call. A nurse can help you decide if you should come in, go to the emergency room, or wait.

• Save your care team's day and night phone numbers in your phone.
• Post the numbers on your fridge and share them with your family.
• Keep a working thermometer at home and know how to use it.
• Ask your team which warning signs matter most for your treatment.
• Keep a list of your medicines and your last treatment date in your wallet or phone.
• Ask for refills a few days before you run out.
• Ask which emergency room your team wants you to use.

Last updated: 2026-10-27. Medically reviewed by Veli Bakalov, MD, medical oncologist (October 2026). General education from Step by Step, the patient portal of HemeOncBuddy.