Many people on chemotherapy (chemo) may experience nausea and vomiting. Many chemo medications cause the release of a substance called serotonin and other chemicals. This release can be a signal that activates the "vomiting center" in your brain.

The nausea and vomiting caused by chemo can be:

  • Acute: Occurs within minutes to the first few hours after chemo administration
  • Anticipatory: Occurs as a conditioned response, meaning it happens in response to stimulus that has caused nausea or vomiting in the past, such as the sight or smells of the treatment room

Certain chemo medicines are more likely than others to cause nausea and vomiting. Chemo medications are classified as minimal, low, moderate, or high in terms of the chance they will cause vomiting. If the chemo prescribed for you is associated with a moderate to high probability of nausea and vomiting, your doctor will likely recommend appropriate support medicines to control the chemo side effects. Discuss your chemo regimen with your doctor and care team. Ask what the likelihood is that you will experience nausea and vomiting as a result of your treatment.

What Can Be Done to Manage Nausea and Vomiting?

Medicines for controlling nausea and vomiting are called antiemetics. Some of these medications block the signal in the brain and gut that causes nausea and vomiting. Your doctor may have you try more than one antiemetic medication before finding the prescription that works best for you.

There are also several things you can do at home to prevent or control nausea and vomiting:

  • Eat 5 to 6 smaller meals, rather than 3 large meals, throughout the day.
  • Eat foods that are easy to digest. Foods that are not as likely to upset your stomach include plain crackers, rice, and toast.
  • Avoid onions, garlic, coffee, and other strong-smelling foods. Avoid being around food as it is being cooked.
  • Wait at least 1 hour after your chemo before eating or drinking anything.
  • Consume foods and drinks at room temperature or cool.
  • If you feel the urge to vomit, try slow, deep breathing.
  • You may be able to distract yourself by reading, watching television, or doing a relaxing hobby.
  • Ask your doctor about medicine for controlling nausea and vomiting during and after chemo.

Ask Your Doctor:


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