A breast cancer diagnosis often comes with a long list of potential treatments and side effects. Many symptoms can be managed at home or discussed at your next clinic visit, but some warning signs require immediate medical attention.
Knowing the difference can help you act quickly and potentially prevent serious complications.
Fever or signs of infection
Cancer treatments such as chemotherapy and some targeted therapies can weaken the immune system. This makes infections more dangerous and sometimes life-threatening.
Learn more about breast cancer treatment and care
Call your care team or seek urgent care if you experience any of the following symptoms:
- Fever
- Chills, shaking or sweats
- A sore throat, cough or burning when urinating
- Redness, swelling or pus around surgical site or port
Infections can progress quickly in people with reduced white blood cells, so prompt treatment is essential.
Sudden shortness of breath
Breast cancer treatments can increase the risk of blood clots. A clot that travels to the lungs (pulmonary embolism) is a medical emergency.
Seek immediate care if you experience:
- Sudden difficulty breathing
- Chest pain, especially when taking a deep breath
- Racing heart or dizziness
- Coughing up blood
These symptoms should never be ignored, even if they seem mild at first.
Severe headaches or neurological symptoms
Any type of cancer, including breast cancer, can spread to the brain. When this happens, it can cause sudden neurological changes.
Go to the emergency room if you notice:
- A severe or unusual headache
- Confusion or trouble speaking
- Vision changes
- Weakness or numbness on one side of the body
- Seizures or loss of consciousness
Rapid evaluation is critical because early treatment can reduce long-term damage.
Uncontrolled nausea and vomiting
Many cancer treatments cause nausea and vomiting, but severe or persistent symptoms can lead to dehydration and become dangerous. If you’ve followed your doctor’s orders to manage these symptoms, including drinking plenty of fluids, but cannot keep anything down, you might need to see a doctor.
Seek urgent care if you:
- Cannot keep fluids down for 24 hours
- Feel dizzy or faint
- Notice very dark urine or minimal urination
- Have persistent diarrhea
Dehydration can worsen quickly and may require IV fluids and medications.
Trust your instincts
Remember that you know your body best. If your condition suddenly worsens or you experience any new or unusual symptoms, it is always appropriate to call your oncology team or go to urgent care. Many cancer centers provide 24-hour phone lines specifically for this purpose.
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