CBD and Chemotherapy

Published: 6 August 2025
Last Updated: 24 July 2026
Last Reviewed: 24 July 2026
Author: Weed Supermarket Editorial Team

What Does Current Research Say?

Chemotherapy is an important treatment for many types of cancer, but it can also produce side effects that affect quality of life. Nausea, pain, reduced appetite, fatigue and sleep disturbance are common challenges experienced by many patients during treatment.

As interest in cannabinoids has increased, researchers have investigated whether compounds such as CBD, THC and CBN may help manage some chemotherapy-related symptoms. While research continues to develop, it is important to separate established medical evidence from areas that remain uncertain.

This article explains what current research says about cannabinoids during chemotherapy and highlights why patients should always discuss cannabinoid use with their oncology team.

Understanding CBD

CBD (cannabidiol) is one of the principal cannabinoids naturally found in Cannabis sativa.

Unlike THC, CBD is not generally associated with the intoxicating effects commonly linked with cannabis.

Researchers continue to investigate CBD across a wide range of medical conditions, including supportive care during cancer treatment.

You can learn more in our guide explaining the CBD Entourage Effect.

Can CBD Help During Chemotherapy?

Several symptoms experienced during chemotherapy have been investigated in relation to cannabinoids.

Areas of ongoing research include:

Nausea and vomiting.
Pain.
Sleep disturbance.
Anxiety.
Appetite changes.
Overall quality of life.

However, current evidence varies considerably depending on the symptom being studied and the specific cannabinoid involved.

Chemotherapy-Induced Nausea and Vomiting

Chemotherapy-induced nausea and vomiting (CINV) is one of the best-studied areas of cannabinoid research.

Prescription medicines containing THC or combinations of cannabinoids have demonstrated benefit for some patients whose nausea has not responded adequately to standard anti-sickness medication.

Evidence specifically supporting CBD alone for chemotherapy-induced nausea remains limited, and further high-quality clinical trials are needed.

Pain Management

Cancer-related pain and chemotherapy-induced nerve pain continue to be areas of active research.

Some studies have investigated cannabinoids for chronic pain, but evidence during chemotherapy remains mixed.

Current evidence does not support concluding that CBD alone consistently relieves chemotherapy-related pain.

Appetite

Loss of appetite can occur during chemotherapy for many different reasons.

Research examining appetite has focused largely on THC-containing medicines rather than CBD.

There is currently insufficient evidence to conclude that CBD reliably improves appetite during chemotherapy.

Sleep and Anxiety

Many people receiving chemotherapy experience difficulty sleeping or increased anxiety.

CBD has been investigated for both areas, although results remain inconsistent.

Some early studies suggest CBD warrants further investigation, but current evidence is insufficient to recommend CBD as an established treatment for chemotherapy-related anxiety or sleep disturbance.

Other Cannabinoids

Researchers continue to investigate several cannabinoids in cancer supportive care.

THC

THC-containing prescription medicines have demonstrated benefits for some patients experiencing chemotherapy-induced nausea and vomiting.

These medicines differ significantly from consumer cannabinoid products and should only be used under appropriate medical supervision.

CBN

CBN (cannabinol) has attracted increasing research interest, particularly regarding sleep.

However, clinical evidence remains limited, and no conclusions can currently be drawn regarding its effectiveness during chemotherapy.

Learn more in our guide: What Is CBN?.

Can CBD Interact With Chemotherapy?

Yes.

One of the most important considerations is that CBD may interact with medicines by affecting enzymes involved in drug metabolism, particularly within the cytochrome P450 system.

Because many chemotherapy medicines rely on these pathways, CBD could potentially alter how certain treatments are processed.

For this reason, patients should always discuss CBD use with their oncologist or specialist cancer team before starting any cannabinoid product.

Possible Side Effects

Although CBD is generally well tolerated by many people, side effects can occur.

Reported side effects may include:

Drowsiness.
Fatigue.
Dry mouth.
Digestive discomfort.
Changes in appetite.
Dizziness.

Individual responses vary considerably.

Product Quality Matters

Independent laboratory testing provides information about cannabinoid products.

Testing may include:

CBD concentration.
Other cannabinoids present.
THC content.
Heavy metals.
Residual solvents.
Microbiological contamination.
Batch consistency.

Laboratory testing helps verify product composition but does not demonstrate effectiveness during chemotherapy.

Read more in our UK Compliance & Laboratory Testing guide.

Isolates and Extracts

Some people choose cannabinoid isolates or extracts because they offer:

Consistent cannabinoid content.
Measurable dosing.
Minimal flavour.
Versatility for use according to manufacturer instructions.

These characteristics relate to product composition and convenience only and should not be interpreted as evidence of greater medical effectiveness.

Learn more about cannabinoid concentrates in our Isolates & Extracts guide.

Related Guides

Frequently Asked Questions

Can CBD treat cancer?

No. There is no evidence that consumer CBD products treat or cure cancer, and they should never replace conventional cancer treatment.

Can CBD help chemotherapy side effects?

Researchers continue to investigate CBD for symptoms such as nausea, pain, anxiety and sleep disturbance, but current evidence remains limited.

Can CBD interact with chemotherapy medicines?

Yes. CBD may affect how certain medicines are metabolised, making discussion with your oncology team essential before use.

Is medical cannabis available in the UK?

Certain cannabis-based medicinal products may be prescribed by specialist clinicians in limited circumstances under UK law.

Are CBD isolates easier to use?

Some people prefer isolates because they provide consistent cannabinoid content and minimal flavour, although this does not imply greater medical effectiveness.

Should I tell my oncologist if I use CBD?

Yes. Always inform your oncology team about any supplements or cannabinoid products you are considering or currently using.

Final Thoughts

Cannabinoids continue to be investigated as supportive therapies for managing certain chemotherapy-related symptoms, particularly nausea, pain and sleep disturbance.

Although some prescription cannabinoid medicines have an established role in specific clinical settings, evidence relating to consumer CBD products remains limited and continues to evolve.

Anyone receiving chemotherapy should discuss cannabinoid use with their oncology team to ensure safe, coordinated care alongside conventional cancer treatment.

Compliance Statement

This article is provided for educational purposes only and does not constitute medical advice. It does not claim that CBD, THC, CBN or other cannabinoids diagnose, treat, prevent or cure cancer. Cannabinoids should never replace chemotherapy or any treatment recommended by your oncology team. Always consult your oncologist, cancer specialist or other appropriately qualified healthcare professional before using cannabinoid products during cancer treatment.