Medicines Used to Treat Nausea and Vomiting

Many drugs or combination of drugs are available to help prevent and control vomiting. These may also control nausea.

Your body has several different pathways that trigger nausea and vomiting. Anti-nausea and vomiting drugs (sometimes called anti-emetics) have been developed to target and block these pathways. Some of these drugs target the vomiting center in the brain, while others work as rescue therapy if the initial nausea medicine doesn’t work. Based on this knowledge, and the treatment’s potential to cause nausea and vomiting, your doctor will recommend certain anti-nausea and vomiting medicines. You might have to try a few different drugs to find the ones that work best for you.

Types of anti-nausea and vomiting drugs

Anti-emetic drugs are grouped by how they work in the body on different types of nausea and vomiting. It's important to remember that the groups of drugs work differently. One drug might not work as well for you as it does for someone else, depending on the type of nausea and vomiting you might have.

• Serotonin (5-HT3) antagonists block the effects of serotonin, a substance that commonly triggers nausea and vomiting. These drugs are effective at controlling acute nausea and vomiting and are usually given before chemo and then for a few days afterward. (Examples: ondansetron, granisetron, dolasetron, palonosetron)
• NK-1 receptor antagonists block the effects of the NK-1 receptor, a receptor that is a part of the vomiting reflex. These drugs help with delayed nausea and vomiting and are sometimes used to help with acute nausea and vomiting. They’re often given with other anti-nausea medicines. (Examples: aprepitant, rolapitant, fosaprepitant)
• Steroids are often given with other anti-emetic drugs to better prevent nausea and vomiting. They might be given before or after treatment. Sometimes steroids are not used for nausea and vomiting because of their side effects that might affect other health problems a patient has. (Example: dexamethasone)
• Dopamine antagonists target dopamine to help prevent this substance from binding to areas in the brain that trigger nausea and vomiting. Many times these drugs are given when nausea and vomiting is not well controlled by other drugs. (Examples: prochlorperazine, metoclopramide)
• Benzodiazepines can help reduce nausea and vomiting by reducing anxiety and helping the person feel more calm and relaxed. These drugs may be more helpful with patients who experience anticipatory nausea and vomiting and are often used in combination with other anti-nausea drugs. (Examples: lorazepam, alprazolam)
• Cannabinoids contain the active ingredient in marijuana. These drugs may be used to treat nausea and vomiting from chemo when the usual anti-emetic drugs don’t work. They also may be used to stimulate appetite. Talk to your doctor about any side effects you might experience while using cannabinoids. (Examples: dronabinol, nabilone)
• Olanzapine is a drug that has been shown to be helpful in reducing nausea and vomiting, especially in combination with other anti-nausea and vomiting drugs. It can make you sleepy, so talk to your doctor about the side effects you might have while using olanzapine.
• Combination anti-nausea medicines include more than one type of anti-nausea drug in one dose. For example, you can get a combination of a serotonin (5-HT3) antagonist with a NK-1 receptor antagonist. This combination is meant to help with both acute and delayed nausea and vomiting.

The drug names given above are only examples. This is not a complete list of the drugs in each group.

Cost of anti-nausea and vomiting drugs

Many of these drugs can be expensive and you might need pre-approval from your health insurance before they will be covered. Others are available as generic drugs and cost a lot less than the name brands. Don’t be afraid to ask your cancer care team about the cost of these drugs, what your options are, and what you might have to pay out of pocket.

It's important to think about how many pills you may need to get you through your treatment. Be sure you talk to your insurance company about how many pills are covered for each prescription, and let your doctor know if you think you might not have enough to get you through until your next appointment.

How are anti-nausea and vomiting medicines given?

There are many ways to take anti-nausea and vomiting medicines. For instance, you may be able to take them:

• Through an IV (intravenously)
• By mouth as a pill or liquid you swallow
• As a tablet that dissolves under your tongue
• As a suppository
• Through a patch that sticks to your skin

Your doctor will consider the following things when deciding the best way to give your anti-emetics:

• How likely it is that the cancer treatment will cause nausea and vomiting
• How bad your nausea and/or vomiting is
• The easiest way for you to take the medicine
• What you prefer
• How quickly the drug will start working
• Your medical insurance coverage (many of these drugs are very expensive, especially in IV form) 

If the drugs used at first don’t work, your doctor can switch you to another drug or add a new drug. Another option is to give the drugs a different way (by a different route). Taking pills by mouth is often the best, easiest, and cheapest way to prevent nausea and vomiting. But if you’re already vomiting, or you can’t swallow and keep things down, the medicine might need to be given another way.

Let your doctor know if you are still having problems despite treatment. Don’t let nausea and vomiting make you feel bad and keep you from getting the nutrition your body needs during treatment. There’s no reason for you to have uncontrolled nausea and vomiting. There are many drugs that can be used to prevent and treat these side effects.

Treating nausea and vomiting caused by cancer medicines

The specific anti-emetic given and how often you take it is based on how likely the chemo or other drug is expected to cause nausea and vomiting. It’s easier to prevent nausea and vomiting than it is to stop it once it starts. No one drug can prevent or control treatment-related nausea and vomiting 100% of the time. This is because treatments act on the body in different ways and each person responds to chemo and to anti-nausea and vomiting drugs differently.

To choose the best treatment plan for you, the doctor will:

• Consider how likely your treatment is to cause nausea and vomiting
• Look at current research and guidelines that tell the doctor what anti-nausea medicines work best for the treatment you're receiving
• Select medicines based on whether the treatment for cancer is known to affect the vomiting center in the brain
• Ask about your history of nausea and vomiting
• Ask how well any anti-nausea medicines have worked for you before
• Consider side effects of the anti-nausea medicines
• Prescribe the lowest effective dose of the anti-nausea medicine before treatment is given
• Make changes as needed to help keep you from having nausea and vomiting

Anti-nausea and vomiting medicines are often given on a regular schedule around the clock. Your doctor might encourage you to take them on a schedule even if you don't have any nausea or vomiting. Sometimes, you may take the medicine on an "as needed" schedule. This means you take the medicine at the first sign of nausea to keep it from getting worse. Ask your cancer care team how you should take these drugs.

• Preventive medication should start before the treatment is given.
• Medication should continue for as long as the cancer treatment is likely to cause vomiting, which may be different for different people based on the type of chemo drug given.

Each time you start a new cycle of chemo, be sure to tell your cancer team what did and didn’t work the last time.

Treating nausea and vomiting caused by radiation therapy

If your radiation treatment is likely to cause nausea and vomiting, your doctor will probably give you medicines to help prevent it each day before you get radiation. Anti-nausea and vomiting medicines may be given by mouth or into a vein, or both.

To choose the best treatment plan, the doctor will:

• Consider how likely the radiation is to cause nausea and vomiting
• Ask about your history of nausea and vomiting
• Ask how well any anti-nausea medicines have worked for you before
• Consider side effects of the anti-nausea medicines
• Prescribe the lowest effective dose of the anti-nausea medicine before radiation therapy is given
• Make drug changes as needed to help keep you from having nausea and vomiting

Anti-nausea and vomiting medicines are often given on a regular schedule around the clock. your doctor may encourage you to take them on a schedule even if you don’t have any nausea or vomiting. Sometimes you may take the medicine “as needed.” This means you take the medicine at the first sign of nausea to keep it from getting worse. Ask your cancer care team how you should take your anti-nausea and vomiting medicines.