What Causes Nausea or Vomiting?

What Causes Nausea or Vomiting?

What is nausea and what causes it?

Nausea is the unpleasant feeling of needing to vomit. There’s an area of the brain called the vomiting centre that controls the feeling of nausea and the need to vomit. It will receive signals from other parts of the body such as the gut and the vestibular system (part of the ear that controls balance), as well as the other parts of the brain such as the chemoreceptor trigger zone (CTZ). These signals stimulate the vomiting centre in the brain and this is why you feel nausea and a need to vomit. 

There are many conditions that can cause nausea.

Some of the common ones include gastroenteritis (infection of the gut), migraine, anxiety,  pregnancy, nausea caused by ear problems, and motion sickness (car or sea sickness). And other rare causes of nausea include tumours in the gut, and brain, as well as infections of the brain.

To start, you’ll get anti-nausea/vomiting medicines based on which chemotherapy (chemo) drugs you are getting. For example, if you’re getting a chemo drug that’s likely to cause nausea and vomiting, you should get anti-emetic that has proven to work best in other people who got that same drug. And if these medicines do not prevent your nausea and vomiting, it’s more important to tell your doctor so you can get different medicines. And you might have to try a few different medicines to find the ones that work best for you.

Learn more about Treating Nausea and Vomiting

Common side effects:

  • Headache
  • Hiccups
  • Diarrhea
  • Constipation
  • Will change the electric activity in the heart (as seen on an EKG)

Most commonly used drugs in this group:

  • Dexamethasone 
  • Methylprednisolone 
  • Steroids may be part of your chemo plan, in which case you might not need them (or they may be given at a decreased dose) as part of anti-emetic treatment. They’re often given the day of chemo, and for few days afterwards.

Common side effects:

  • Trouble sleeping
  • Increased appetite
  • Fluid retention; swelling of the hands, face and feet
  • Weight gain
  • Increased blood sugar levels