Nausea and Vomiting
Nausea is an unpleasant sensation of being queasy and feeling the need to throw up. These side effects are separate, but people often experience them together. They can also worsen other symptoms, such as pain, insomnia, cognitive dysfunction, fatigue and appetite challenges. If vomiting is not controlled and becomes severe, it can lead to dehydration, which is a lack of essential fluids and minerals in your body. Severe symptoms can even interrupt your treatment plan.
What causes nausea and vomiting?
When treatment damages the cells lining the inside of the stomach, the cells send signals to a vomiting center (the fourth ventricle) in your brain, which then sends signals to trigger nausea and vomiting. Drug therapies (most commonly chemotherapy) may trigger the vomiting center directly. The dose used, how often the drug is given, and how it is given are factors in the likelihood of nausea and vomiting occurring. Your medical team may refer to it as chemotherapy-induced nausea and vomiting (CINV). In addition, some cancers, dehydration, infection, pain, other diseases and anxiety can also lead to nausea and vomiting. These are common side effects of other types of medication, especially strong pain medications, such as opioids. Surgery and radiation therapy (in high doses, as well as radiation aimed at the gastrointestinal tract, liver or brain), can also cause these symptoms.
When do nausea and vomiting typically occur?
Nausea and vomiting related to drug therapies are described as either acute or delayed. Acute begins minutes to hours after the drug is given, peaks in 5 to 6 hours and resolves within 24 hours. Delayed begins more than 24 hours after the drug is given, peaks in 48 to 72 hours and resolves within 3 to 7 days. These side effects may also be described as anticipatory. They can occur before a drug dose is given and usually happen in people who have had severe nausea and vomiting during a previous experience with a drug therapy. With prescription opioids, this side effect usually occurs within a few hours of a dose.
How you can manage nausea and vomiting.
These symptoms are easier to prevent than to control once they have started. If possible, discuss this with your health care provider before starting treatment. You may want to supplement anti-nausea drugs with a non-drug approach such as progressive muscle relaxation, biofeedback, guided imagery or acupuncture. Taking supportive care drugs in conjunction with your treatment may also help prevent nausea and vomiting.
Changes to your eating habits may help:
- Eat several small meals throughout the day rather than three big meals.
- Try eating a light meal a few hours before your scheduled treatment.
- Drink plenty of fluids in small amounts throughout the day.
- Avoid unpleasant odors, as they can trigger nausea. Surround yourself with pleasant scents.
- Rest after eating, but don’t lie flat.
- Eat bland foods such as toast or crackers.
- Try ginger chews, drinks or capsules to settle an upset stomach.
- Smell peppermint in some form. Essential oils are often used.
Anesthesia given during surgery can also cause nausea and vomiting. Before surgery, certain anti-nausea medications can be given preventively by IV. Sometimes, anti-nausea drugs are prescribed to be taken before drug therapy starts and at specific intervals after treatment for as long as the risk of vomiting is expected.
Prevention of nausea and vomiting related to radiation therapy follows a similar approach. If you are to have total body radiation or radiation to the upper abdominal area, your health care provider will prescribe an anti-nausea drug to be taken before your scheduled treatment and for a period of time after treatment. For them to be most effective, it is important that they are taken at the prescribed intervals and not on an as-needed basis. Some are best for mild nausea and vomiting, and others are appropriate for more severe cases; some are effective for acute symptoms and others for delayed symptoms. Most can be given as either a pill or an injection. Although both forms are equally effective, intravenous drugs usually act more quickly.
When to call your health care provider.
Tell your health care provider if you are still experiencing nausea and vomiting even after taking the anti-nausea drug as prescribed. This type of nausea and vomiting is known as breakthrough, and you may need a different drug or an increased dose in order to control these symptoms. If you are planning to attend a special event, let your health care provider know. Sometimes your treatment can be adjusted to make it easier for you to attend these special occasions without having to worry about feeling too ill to enjoy them. When you are away from home, be prepared by locating the nearest restroom, just in case.
Call your health care provider right away if you experience any of the following:
- More than 3 episodes of vomiting per hour for at least 3 hours.
- Vomiting blood or something that looks like coffee grounds.
- Inability to take more than 4 cups of fluid or ice chips in 24 hours or any solid foods for more than 2 days.
- Inability to keep your medications down.
- Weakness or dizziness.
