What is Nausea and Vomiting?
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Although nausea and vomiting commonly occur together, they are separate conditions. Nausea is an unpleasant wavelike feeling in the back of the throat or stomach that may or may not result in vomiting. Vomiting is the forceful emptying of the contents of the stomach through the mouth.
How does Chemotherapy cause Nausea and Vomiting?
The exact mechanism by which chemotherapy drugs cause nausea and vomiting is not completely known. One theory is outlined below:
- 1. Chemotherapy is administered and enters the bloodstream.
- 2. Chemotherapy damages certain cells in the lining of the intestine.
- 3. A chemical messenger known as serotonin is released from the damaged cells. Serotonin then binds or attaches to special receptors or nerve cells that are part of the intestines' nerve network. These nerve receptors are known as 5-HT3 receptors.
- 4. The serotonin signal from the nerve then sends a message to a special area in the base of the brain called the chemoreceptor trigger zone (CTZ). This area sends a signal to the vomiting center (VC) in the brain causing the abdominal muscles to contract, and then vomiting begins.
Types of Nausea and Vomiting:
- Acute-onset (same day) nausea and vomiting usually occurs a few minutes to several hours after the chemotherapy treatment. Acute nausea and vomiting are more likely to occur in patients who have experienced nausea and vomiting after previous chemotherapy sessions, in female patients, younger patients and those who drink little or no alcohol.
- Delayed nausea and vomiting may occur 1 to 5 days after chemotherapy and may be more likely to occur if you have received certain types of chemotherapy. Preventing delayed nausea and vomiting is important and starts by providing the best medication to prevent nausea and vomiting on the first day of treatment.
- Anticipatory nausea and vomiting is a conditioned response resulting from episodes of nausea and vomiting from prior cycles of chemotherapy. Patients then associate certain smells, thoughts or sights with that bad experience. They can feel nauseated or even vomit when a smell or sight reminds them of their previous chemotherapy experience. Anticipatory nausea and vomiting are best prevented by giving patients the most effective antiemetics before their first experience with chemotherapy.
Helpful Tips
- If you are hungry and want to eat before chemotherapy, eat a low-fat snack or light meal.
- In general, patients receiving chemotherapy should avoid dehydration. Patients are encouraged to drink 6 to 8 ounce beverages daily, including water and juice. Some experts recommend ginger ale, which may have natural anti-nausea properties.
- Consider avoiding caffeine or alcohol.
Managing Side Effects
- Try to eat small frequent meals rather than three large meals.
- Add extra calories and protein to meals. Nutritional supplements may be helpful.
- Avoid any odors that upset your stomach (e.g. cooking odors, smoke or perfume).
- Avoid lying flat for at least 2 hours after meals. Pile up pillows to elevate your head and shoulders.
- Do not eat fatty or fried foods
Patient Risk Factors
- Age: Young adults are more likely to develop nausea and vomiting than older adults.
- Gender: The prevalence of nausea and vomiting is higher in women.
- No or minimal use of alcohol: This is associated with a higher risk of nausea and vomiting.
- History of nausea and vomiting: Patients with a history of motion-sickness or a prior history of nausea and vomiting associated with chemotherapy are at higher risk for future problems with nausea and vomiting associated with chemotherapy.
- Do not eat fatty or fried foods
Questions to Ask Your Doctor
- What type of chemotherapy drugs will I receive and how will I tolerate them?
- What are the chances these drugs will cause me to have nausea and vomiting?
- If I do experience nausea and vomiting, how long will it last? When do I call the doctor?
- What are the signs of dehydration?
- Does my background and history increase my risk of experiencing nausea and vomiting?
- What types of medications will I be given to reduce my chance of experiencing nausea and vomiting?
- Before I receive my chemotherapy, what can I do to reduce my chances of experiencing nausea and vomiting?
