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Nausea and vomiting

Feeling nauseous? Experiencing vomiting? This information will help you understand why you are nauseous, what you can do to help, and when you should call your family health team.

What do I need to know about nausea, vomiting and cancer?

  • "Nausea" is an unpleasant feeling in the back of your throat and stomach that may or may not happen with vomiting
  • Other ways people describe nausea include "feeling sick to my stomach", queasy, and "having butterflies"
  • Other symptoms you may have with nausea will be more saliva, feeling light-headed, clammy skin, and a fast heart rate
  • Vomiting or "throwing-up" happens when stomach contents are brought up through the mouth
  • Retching or "dry heaves" happens when the stomach is empty and nothing comes up
  • 40-70% of people with cancer will have nausea and vomiting at some point during their illness
  • If possible, stopping nausea before it starts is the most important step

What causes nausea?

There are many causes of nausea and vomiting. Often two or more causes happen at the same time, including:

  • chemotherapy
  • radiation therapy
  • medications
  • constipation
  • cancer effects
  • infection
  • movement-related (motion sickness)
  • anxiety

When should I talk to my health care team about my nausea and vomiting?

  • If your nausea is severe and goes on for more than 48 hours despite taking anti-nausea medications
  • If you vomit more than 10 times in 24 hours

What should my health care team know about my nausea and vomiting?

  • If you have nausea and vomiting you should contact your health care team
  • Bring a list of all your medications and treatments such as chemotherapy or radiation therapy
  • Take note of any patterns of the nausea and vomiting, such as just after eating, or at a certain time of day
  • If you are vomiting, take note of colour and amount

What do I need to know about the medications used for nausea and vomiting?

When possible, medications are given for nausea and vomiting.

  • It is important that you use the anti-nausea medications given to you by your doctor. It is always easier to stop symptoms before they start.
  • No single medicine can control nausea and vomiting 100% of the time.
  • For minor nausea and vomiting, medications may be taken as you need them.
  • For bad nausea and vomiting medications are taken on a regular schedule around the clock, and “breakthrough” or “in between” doses may be needed for nausea and vomiting that is hard to control.
  • Many different types of medication may be used at the same time if symptoms are more severe.

Is there anything I can I do to stop or lessen my nausea?

  • Some people treat the anxiety that can happen with nausea and vomiting. These treatments work by making you feel more relaxed, distracting you and helping you feel more in control of your symptoms
  • Some of these treatments are progressive muscle relaxation, acupuncture, hypnosis and guided mental imagery.

Your health care provider can prescribe a type of drug call an “anti-emetic” to prevent or reduce nausea. It is easier to prevent nausea than to treat it once it starts. It is important to take the medicine as directed by your health care team. You may need to try different things to find the one that works best for you.

What are some other things I can do to prevent or help with nausea and vomiting?

  • Eat smaller, more frequent meals throughout the day. Eat slowly.
  • Nibble on dry foods, such as crackers, toast, dry cereals or bread sticks. Try this as soon as you wake up and many times during the day.
  • Limit the use of caffeine, including colas and other caffeinated soft drinks such as coffee drinks and tea
  • During the day sip liquids such as juices, Boost Fruit Beverage, frozen juice bars, popsicles, flat ginger ale, sports drinks, broth, herbal teas. Try cool liquids, which may be easier to drink than hot or cold liquids
  • Ask someone else to cook for you if cooking smells upset your stomach
  • Try not to eat in a room that is warm or that has cooking odours or other smells. Make sure you have fresh air by opening a window or use a fan
  • Wear loose clothing
  • Try not to eat or be around foods with a strong smell. Eat foods that are served cold or at room temperature if smells bother you
  • Try not to eat foods that are very sweet, greasy, fried or spicy
  • Keep your mouth clean by brushing your teeth at least twice a day. This can help with tastes in your mouth that make you feel sick to your stomach
  • Try not to lie down flat for at least an hour after eating
  • Ginger may help nausea. Try sipping on ginger tea or flat ginger ale through the day, using fresh ginger in your cooking or sucking on ginger-flavoured candies


If you continue to have problems with keeping your fluid and food down or if you have other side effects that are stopping you from eating or drinking, ask your health care provider about a referral to a dietician at the Odette Cancer Centre or call 416-480-4623.

You can find more information about nausea and vomiting by visiting the Patient Education Learning Centre (PEARL) on the 1st floor of the Odette Cancer Centre or by emailing patienteducation@sunnybrook.ca or calling 416.480.4534

Patient symptom management guide

Click here to download a copy of Cancer Care Ontario’s patient symptom management guide.
Copies of this resource are also available in simplified Chinese, traditional Chinese, French, Spanish and Tamil.
Email patienteducation@sunnybrook.ca to ask for a translated copy.