The short answer
Chemotherapy is often given in cycles, with treatment followed by a rest period so your body can recover. How often and how long you receive it depends on your cancer and the drugs used. Your doctor checks how it is working with exams and scans, not by your side effects.
Chemotherapy is often given in cycles: a period of treatment followed by a period of rest.
Treatment schedules vary widely and depend on your cancer, the drugs, and how your body responds.
It is best not to skip a treatment, but your doctor may adjust your schedule if you have certain side effects.
Your doctor uses exams, blood tests, and scans — not your side effects — to see if chemotherapy is working.
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The full explanation.
The simple version
If you are starting chemotherapy, it helps to know what a typical course of treatment looks like. Chemotherapy is rarely a single event. It usually happens over weeks or months, often in a pattern of treatment and rest.
Chemotherapy follows a schedule that your team designs around your cancer and how your body responds.
Understanding cycles
Chemotherapy is often given in cycles. A cycle is a period of chemotherapy treatment followed by a period of rest.
For instance, you might receive chemotherapy every day for one week, followed by three weeks with no chemotherapy. Those four weeks make up one cycle. The rest period is not wasted time — it gives your body a chance to recover and build new healthy cells before the next round.
How often and how long
Treatment schedules vary widely. How often and how long you get chemotherapy depends on:
- your type of cancer and how advanced it is
- whether the goal is to cure your cancer, control its growth, or ease symptoms
- the type of chemotherapy you are getting
- how your body responds to the chemotherapy
Because these factors differ from person to person, two people with the same cancer may have different schedules.
If you need to miss a treatment
It is best not to skip a chemotherapy treatment. But sometimes your doctor may change your schedule if you are having certain side effects. If this happens, your doctor or nurse will explain what to do and when to start treatment again.
Talk to your team before skipping or delaying a treatment on your own.
How chemotherapy may affect you
Chemotherapy affects people in different ways. How you feel depends on:
- the type of chemotherapy you are getting
- the dose you are getting
- your type of cancer
- how advanced your cancer is
- how healthy you are before treatment
Since everyone is different and people respond in different ways, your doctor and nurses cannot know for sure how you will feel during chemotherapy.
The most common side effect is fatigue, which is feeling exhausted and worn out. You can prepare for it by asking someone to drive you to and from treatment, planning time to rest on the day of and the day after chemotherapy, and asking for help with meals and childcare.
How you will know if it is working
You will see your doctor often. During these visits, they will ask how you feel, do a physical exam, and order medical tests and scans. Tests might include blood tests, and scans might include MRI, CT, or PET scans.
You cannot tell if chemotherapy is working based on its side effects. Some people believe that severe side effects mean chemotherapy is working well, or that no side effects mean it is not working. The truth is that side effects have nothing to do with how well chemotherapy is fighting your cancer.
Your care team uses exams and scans — not how rough you feel — to judge progress.
Eating and working during treatment
Chemotherapy can damage the healthy cells that line your mouth and intestines and cause eating problems. Tell your doctor or nurse if you have trouble eating. You might also find it helpful to speak with a dietitian.
Many people can work during chemotherapy, as long as they match their work schedule to how they feel. If your job allows, you may want to see if you can work part-time or from home on days you do not feel well. Many employers are required by law to change your work schedule to meet your needs during cancer treatment. A social worker can explain more about these laws.
Words to know
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Common questions
▸What is a chemotherapy cycle?
A cycle is a period of chemotherapy treatment followed by a period of rest. For example, you might receive chemotherapy every day for one week followed by three weeks with no chemotherapy. Those four weeks make up one cycle. The rest period gives your body a chance to recover and build new healthy cells.
▸How often will I get chemotherapy?
Treatment schedules vary widely. How often and how long you get chemotherapy depends on your type of cancer and how advanced it is, whether the goal is to cure, control, or ease symptoms, the type of chemotherapy, and how your body responds.
▸What happens if I miss a treatment?
It is best not to skip a chemotherapy treatment. Sometimes your doctor may change your schedule if you are having certain side effects. If this happens, your doctor or nurse will explain what to do and when to start again.
▸How will I know if the chemotherapy is working?
You will see your doctor often. During these visits, they will ask how you feel, do a physical exam, and order tests and scans such as blood tests, MRI, CT, or PET scans. You cannot tell if chemotherapy is working based on its side effects.
▸Will chemotherapy make me feel a certain way?
Chemotherapy affects people in different ways. How you feel depends on the type and dose of chemotherapy, your type of cancer, how advanced it is, and how healthy you are before treatment. Because everyone is different, your team cannot know for sure how you will feel.
▸Can I work while getting chemotherapy?
Many people can work during chemotherapy as long as they match their work schedule to how they feel. If your job allows, you may be able to work part-time or from home on days you do not feel well. Many employers are required by law to adjust your schedule during cancer treatment.
Questions to ask your doctor
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