Chemotherapy-Induced Nausea and Vomiting (CINV) and Medical Cannabis

What Causes Chemotherapy-Induced Nausea and Vomiting?

The cause of chemotherapy-induced nausea and vomiting is the activation of the chemoreceptor trigger zone from chemotherapy circulating in the blood, this triggers a certain area of the brain and sends signals to other parts of the body, such as the stomach and intestines.

Many people with cancer may also experience nausea and vomiting due to cancer itself, other cancer treatments, constipation, infection, or poor liver and/or kidney function. However, these are not referred to as chemotherapy-induced nausea and vomiting.

Symptoms of Chemotherapy-Induced Nausea and Vomiting

The symptoms of chemotherapy-induced nausea and vomiting can vary from mild to severe. Mild nausea and vomiting are often uncomfortable however, doesn’t have significant harm to your overall health. Whereas more severe nausea and vomiting can result in health problems such as dehydration and weight loss, as well as fatigue.

What are the different types of Chemotherapy-Induced Nausea and Vomiting?

The different types of chemotherapy-induced nausea and vomiting are classified according to the time of onset.

• Acute – occurring 24 hours after chemotherapy.
• Delayed – occurring 1-5 days after chemotherapy.
• Anticipatory – nausea and vomiting precedes the administration of chemotherapy as a conditioned response due to previous negative experiences with chemotherapy.

Treatment for Chemotherapy-Induced Nausea and Vomiting

In terms of treatment, serotonin receptor antagonists form the basis of treatment for chemotherapy-induced nausea and vomiting.

However, other types of treatment and medication can be an option:

• Steroids and neurokinin 1 receptor antagonists are other anti-sickness medications used for chemotherapy-induced nausea and vomiting.
• Other classes of anti-sickness medications are commonly used in combination with the drugs listed above.
• Nabilone, a synthetic cannabinoid, is licensed as an add-on medication for chemotherapy-induced nausea and vomiting which persists despite optimised conventional anti-sickness medications.

Medical Cannabis for Chemotherapy-Induced Nausea and Vomiting (CINV)

While conventional treatments such as corticosteroids, serotonin receptor antagonists, and neurokinin receptor antagonists are typically the first line of defence against CINV, some patients do not respond adequately to these options. In such cases, cannabinoids, including nabilone and dronabinol, may be considered. Limited studies suggest that these cannabinoids, which contain the active component of tetrahydrocannabinol (THC), may be used for patients with CINV.

For eligible patients with CINV, medical cannabis may be appropriate as part of a broader treatment plan. However, as with any new treatment, it’s essential to consult with a clinician to determine the best approach for your individual needs.