Treatment cycles and courses of treatment

Cancer drugs such as chemotherapy are usually given in cycles over several months. A series of cycles is called a course of treatment.

Length of treatment

Several things affect the length of your treatment. These include the:

  • type of cancer
  • stage of the cancer
  • types of drugs that you’re having
  • side effects the drugs might cause
  • time you’ll need to recover from side effects

Treatment cycles and courses of treatment have been developed through clinical trials. These trials have helped doctors determine which treatments have the most benefit with the least side effects.

Treatment cycles

You usually have cancer drug treatment in cycles. A cycle means that you have a single cancer drug or a combination of drugs and then have a rest to allow your body to recover. 

You might have some chemotherapy drugs as a drip over a day or two and then have some time with no treatment. The treatment and rest time make up one treatment cycle. When you get to the end of the cycle, it starts again with the next cycle. 

If you have some cancer drugs as tablets, you might take them every day for the whole cycle or just for a few days or weeks and then have a rest period.

How long is a treatment cycle?

Depending on the drug or combination of drugs, an individual treatment may last from a few hours to a few days.

How often do you have a cycle of treatment?

Your treatment cycles might be weekly or take 2, 3, or 4 weeks or more, depending on the drugs and your treatment plan. Some treatment cycles are quite complicated. 

How many cycles of treatment do you have?

A series of cycles of treatment is called a course. A treatment course often takes 3 to 6 months but can be more or less.

You would probably have between 4 to 8 treatment cycles during that time.

More information

We have more information on treatment and support if you have been diagnosed with cancer.

  • Cancer: Principles and Practice of Oncology (12th edition)
    VT DeVita, TS Lawrence, SA Rosenberg
    Wolters Kluwer, 2023

  • Cancer and its Management (7th edition)
    J Tobias and D Hochhauser
    Wiley-Blackwell, 2015

  • Chemocare

    Accessed June 2023

Last reviewed: 
28 Jun 2023
Next review due: 
28 Jun 2026

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