What causes nausea and vomiting?
Researchers do not know exactly why some chemotherapy drugs cause
nausea and vomiting. They believe there are several ways that this can happen.
Some drugs may affect the parts of your spinal cord or nervous system that
trigger nausea and vomiting. Some drugs may cause nausea and vomiting by
irritating the lining of your digestive system.1
Sometimes you have nausea from when you had chemotherapy before. Your brain
remembers this and expects nausea when you have chemotherapy again.
Chemotherapy drugs are ranked according to how often they cause
nausea and vomiting. Some cause very little of those side effects. Also, some
people are more likely than others to get sick. Your doctor will consider many
things about you, your treatment, and your cancer to decide if you are likely
to feel sick.
Chemotherapy is more likely to make you feel sick if you:2
- Are female.
- Are younger than
50.
- Have a history of motion sickness.
- Have had nausea
or vomiting with previous cancer treatments.
- Do not drink
alcohol.
- Have a large tumour.
Whether you have nausea and vomiting may also depend on:
- What types of chemotherapy drugs you get. Some
of these drugs are more likely to cause nausea and vomiting than
others.
- How large a dose you get. High doses are more likely to
cause nausea and vomiting.
- When and how often you get chemotherapy.
If the time between treatments is short, your body has less time to recover
from the nausea and vomiting before you get your next dose.
- How the
drugs are given. A drug that is given through your vein (IV) may cause nausea and vomiting sooner than a pill
that is swallowed, because your body will absorb the IV drug
faster.
- Individual differences. Not every person reacts the same to
the same medicine.
- The antinausea medicine you are taking. If it
isn't working for you, you may need to try a different one.
You may feel sick shortly after your chemotherapy treatment begins.
Or you may not feel sick until a day or two later. You may not feel sick at
all. As soon as you start to feel sick, tell your doctor.
Many people start feeling sick before a treatment session even
begins. This is called anticipatory nausea and vomiting. Any little thing—the
smell of an alcohol swab, the sight of a nurse's uniform, the sounds of the
treatment room—may trigger nausea. This usually doesn't happen until after the
third or fourth treatment session. Learning how to control anticipatory nausea
and vomiting is important, because it can make nausea and vomiting more severe
once the chemotherapy actually starts.
Test Your Knowledge
Nausea and vomiting are unavoidable side effects of
cancer treatment.
- True.
- False.
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Why is it important to control nausea and vomiting?
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Controlling nausea and vomiting caused by chemotherapy