Treating the cause of your fever

Treatment for a fever will depend on what's causing it. You usually have to go to hospital for tests and an assessment. You might need to stay in hospital for your treatment or you may be able to have it at home.

Treating a fever caused by the cancer itself

Fevers caused by the cancer itself often stop when you have successful cancer treatment.
Your doctor will also try to relieve your fever symptoms. 

Treating infections

The treatment you have depends on the type of infection you have.

Bacterial infection

Bacterial infections are usually treated with antibiotics. They kill the bacteria or prevent them from spreading around the body.  You have blood tests and possibly some swabs if your doctor thinks you might have an infection. 

Then you will start a course of broad spectrum antibiotics. These are antibiotics that can fight a wide range of different infections. It's very important to treat the infection immediately.

Your doctor will know more about what is causing your infection when your test results come back. This can sometimes take a few days. Your doctor will change the antibiotics you are taking if they are not right for the infection you have. 

You might continue with broad spectrum antibiotics. This is to try and prevent other infections from developing.

You're most likely to have antibiotics into a vein in your arm (intravenously) if you have an infection while you have a low white cell count. You have them until the signs of infection have gone.

Antibiotics can also be given:

  • by mouth - with tablets, capsules, or liquids
  • by injection into a muscle
  • topically- these are creams and lotions you put on and around the skin in the area of infection

There are many types of broad spectrum antibiotics. Your doctor will tell you what antibiotics you will have and the possible side effects.

Viral infection

Some viral infections are treated with anti virals.

Aciclovir is a drug for viral infections, such as herpes simplex or varicella zoster.

Drugs called ganciclovir and foscarnet (Foscavir) can treat a virus called cytomegalovirus. Foscarnet is also useful in treating the herpes simplex virus that is not responding to aciclovir.

Fungal infection

Fungi can live in our bodies without usually causing any problems. But it can cause problems if a fungal infection occurs when your immune system is weak.

A common fungal infection in people with cancer is Candida (thrush). You're more at risk from oral (mouth) thrush if you have a sore mouth from chemotherapy or radiotherapy. You may notice white patches with red and sore skin underneath. 

Fungal infections are treated with anti-fungal drugs, for example, nystatin or fluconazole. Your healthcare team will tell you more about any antifungal treatment if you need it. Including the side effects. 

Treatment for other causes of fever

Reaction to a blood transfusion

Your nurse stops your blood transfusion straight away if you have a reaction to the blood. For example, a high temperature. You might need to have other medication to stop the reaction.

Drug side effects

Fever caused by side effects of drugs is treated by stopping or changing your medication.

Treatment at home

People with a low risk of becoming very unwell from an infection might be able to go home and take tablets to treat the infection. Your healthcare team looking after you will let you know if this is suitable for you. They will also tell you what to look out for and what to do if you do become unwell.

It's very important that you call your hospital advice line or go back to the hospital straight away if you do have any problems.

Preventing fever and infection

You might have antibiotics to try to help prevent infections, if you have a low white blood cell count. These are called prophylactic (pronounced prof-ill-ak-tick) antibiotics.

Growth factors

You might have growth factor drugs. Growth factors are natural substances. They stimulate the bone marrow to make blood cells. Some of these substances are now made artificially. They are given as treatments to increase the number of white blood cells and stem cells in the blood. This can reduce the time you are at risk of infection when having chemotherapy.

Not everyone on chemotherapy needs growth factor injections. It depends on your disease and the effects of the chemotherapy treatment you are having.

  • Electronic Medicines Compendium
    Accessed February 2023

  • Cancer: Principles and Practice of Oncology (11th Edition)
    V T Devita, T S Lawrence and S A Rosenberg
    Lippincott Williams and Wilkins, 2019.

  • Neutropenic sepsis: prevention and management of neutropenic in people with cancer
    National Institute for Health and Care Excellence (NICE) September 2012.

  • Management of febrile neutropaenia: ESMO Clinical Practice Guidelines

    J. Klastersky  and others

    Annals of Oncology, 2016. Supplement 5, v111–v118. 

  • The information on this page is based on literature searches and specialist checking. We used many references and there are too many to list here. If you need additional references for this information please contact patientinformation@cancer.org.uk with details of the particular risk or cause you are interested in. 

Last reviewed: 
14 Feb 2023
Next review due: 
14 Feb 2026

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