Nausea and vomiting from chemotherapy

Nausea (feeling sick or like you need to be sick) and vomiting are common side effects of chemotherapy. These can significantly affect your quality of life.

You’ll be given medication to prevent and control nausea. You may have this when you have chemotherapy and after each treatment, as needed.

You can also do things to help manage this often challenging side effect.

It is important to tell your treating team if you have nausea or vomiting so they can give you the right medications.

Medications that can help with nausea

Anti-nausea drugs are called anti-emetics. 

They work in different ways, so if one isn’t effective, another one may be. Tell your doctor if you don’t think your medicine is working and they can try something else.

You will often be given an anti-emetic before your chemotherapy starts if your drug is likely to make you feel sick. Not all chemotherapy drugs cause nausea and vomiting.

With some chemotherapy drugs, nausea doesn’t start until at least 24 hours after treatment (‘delayed onset’).

In this case, your doctor may recommend you take anti-nausea drugs regularly for the first 2 to 4 days. It is important you take this medication even if you feel well because it’s easier to prevent nausea than treat it.

‘Anticipatory’ nausea and vomiting

If chemotherapy has caused nausea or vomiting before, some people can feel sick or vomit before their next treatment starts. This is called ‘anticipatory’ nausea and vomiting – you expect or anticipate the feelings, even before chemotherapy starts.

Common causes or triggers are:

• the smell or sounds of the chemotherapy treatment room
• entering the room where you have treatment.

Talk to your treating team so they can help you manage this. Relaxation, mindfulness and hypnosis can be helpful but sometimes you may need medication.

If nausea continues or becomes worse

There are many different anti-emetic drugs available. If the one you are taking does not control your nausea or vomiting, your specialist can prescribe a different one. It may take several tries to find the one that works best for you.

If your nausea becomes worse or lasts a long time, you may be given another anti-emetic. Doctors may suggest you take it before meals, especially if your treatment is affecting your appetite.

Contact your doctor if:

• nausea or vomiting lasts for more than 24 hours
• anti-nausea medication does not help
• you can’t eat or drink enough because of these side effects.

It’s important you do not become dehydrated. Contact your doctor so they can give you the treatment you need.

Other ways to manage nausea and vomiting

You can take some easy steps to help reduce nausea and vomiting:

• Eat small, frequent meals.
• Avoid food that is fried, high in fat, or has a strong smell.
• Rest before and after eating.
• Sip fluids (especially water) regularly throughout the day.
• Try fizzy drinks such as soda water, dry ginger ale or lemonade.
• Take the anti-nausea drugs at the recommended times, even if you don't feel sick.
• Talk to a dietitian for advice on foods to avoid or changes to your diet to help reduce nausea.

Complementary therapies such as relaxation therapy, hypnosis and acupuncture can also help to manage nausea and vomiting. Read about complementary therapies.

Tips to track your side effects

A diary of your nausea or vomiting can be helpful in your specialist appointments. Record details such as:

• how long after anti-nausea medication you felt unwell
• what medication you took
• whether the medication was effective.

Use BCNA’s free Tracker tool, available with a My Journey account. You can take all the relevant information to your next appointment. It helps your specialist change your medication to control your side effects better.