Cannabinoids for Chemotherapy Nausea: Where Nabilone and THC–CBD Fit

Medical cannabis collection · Sources reviewed 11 October 2026

Persistent nausea and vomiting during chemotherapy are among the better-defined medical uses for certain cannabinoid medicines. Their place is usually an addition to an appropriate anti-sickness regimen when that regimen has not been sufficient. This is a more precise claim than saying cannabis is a general treatment for nausea.

“Consider nabilone as an add-on treatment for adults”

NICE NG144, recommendation 1.1.1

Excerpt: the recommendation concerns adults with chemotherapy-related nausea and vomiting that persists despite optimised conventional antiemetics.

Why the existing anti-sickness plan comes first

Different chemotherapy regimens create different risks of nausea and vomiting. The oncology team plans prevention and rescue treatment around that risk and the person’s previous experience. Persistent symptoms call for reassessment of the regimen and possible contributing causes, rather than an assumption that a cannabinoid should replace established treatment.

NICE’s rationale also explains a limitation in the older cannabinoid literature: many studies used antiemetic comparisons that no longer reflect modern practice. The appropriate question is whether adding the medicine helps despite current care, not simply whether it beats an inadequate historical comparison. NICE rationale and evidence discussion.

What a newer trial adds

A 2024 trial reported results for 147 evaluable adults with persistent chemotherapy-related nausea or vomiting despite guideline-consistent prevention. Oral THC:CBD was added to their usual antiemetics. Complete response occurred in 24% with THC:CBD and 8% with placebo: an absolute difference of 16 percentage points. Grimison and colleagues, 2024.

Here, complete response meant no vomiting or retching and no rescue medicine during the specified five-day period. It did not mean that every cancer symptom disappeared. Sedation, dizziness and transient anxiety were more frequent with THC:CBD. The trial therefore supports a potential benefit together with additional harms, rather than an uncomplicated promise of relief.

Nabilone, THC and CBD are not interchangeable

Nabilone is a synthetic cannabinoid medicine. It is not another name for CBD oil. Likewise, a trial of a particular THC:CBD capsule does not establish equivalence to dried flower, a different ratio or a consumer product. The preparation, route and accompanying antiemetics are part of what was tested.

The ASCO guideline supports a possible role for cannabinoids in refractory chemotherapy-related nausea and vomiting, while recognising uncertainty in other cancer-related supportive-care outcomes. ASCO guideline, 2024. UK prescribing decisions should still use the relevant product information and local clinical arrangements.

Record both the symptom and the trade-off

A person might vomit less yet remain too nauseated to eat, or feel relief at the cost of troublesome sedation. Naming those outcomes helps the team adjust the plan. It also makes the next chemotherapy cycle easier to prepare for than a simple note that the treatment worked.

When this needs prompt attention

Persistent vomiting, inability to retain fluids or essential medicines, or signs of dehydration should be discussed promptly with the oncology team using its urgent-contact instructions. Not every episode is simply an expected chemotherapy effect, and cannabinoids can themselves be associated with unwanted gastrointestinal effects.

The strongest case for their use is a defined problem, an agreed add-on treatment and a review of both symptom control and adverse effects. That respects the seriousness of the symptom without turning a specific evidence base into a recommendation for every cannabis product.

Educational information, not an individual prescribing plan. Decisions about medicines belong with the treating clinician. External reference links open in a new tab.