Medical Cannabis May Improve Quality of Life for Cancer Patients | Research

The takeaway

A review of 16 studies suggests medical cannabis can improve pain, sleep, appetite, mental health, and reduce opioid use in cancer patients, though more rigorous trials are needed.

Cancer patients and caregivers, oncologists, palliative care providers, and anyone exploring cannabis for cancer symptom management.

What the researchers found

Medical cannabis use in cancer patients was associated with improvements in mental health, sleep, appetite, and pain management. It also decreased nausea, vomiting, and use of other medications including opioids. Increased survival time and cognitive function improvements were also observed. Adverse effects were generally mild or moderate.

Why it matters

Cancer patients often face poor quality of life from both the disease and its treatment. If medical cannabis can meaningfully improve multiple symptoms simultaneously while reducing opioid dependence, it could become an important supportive care option.

The numbers in context

267 articles identified, 16 selected. Only 4 were randomized clinical trials. Both THC and CBD (full spectrum) were commonly used. Varied intervention durations across studies. Improvements noted in pain, sleep, appetite, mental health, nausea/vomiting. Opioid use reduction observed.

How the study worked

Critical review of PubMed, LILACS, Scopus, VHL, and Embase databases. Inclusion criteria: English, Spanish, or Portuguese; published through January 2025; full content available. 267 articles identified, 16 selected for final analysis. Both THC and CBD (full spectrum) products evaluated.

What this study cannot tell us

Only 4 of 16 studies were RCTs — most were lower-quality designs. Heterogeneous cannabis products, doses, and outcome measures. Potential interaction with chemotherapy noted but not fully characterized. Insufficient evidence for systematic review or meta-analysis.

How to read the evidence

Critical review with consistent findings across studies, but only 4 RCTs among 16 studies limits strength of conclusions.

When this study was published

Published in 2026, reviewing literature through January 2025.

The bigger picture

Cancer supportive care is an area where medical cannabis shows the most consistent promise across multiple studies. The potential to reduce opioid use while improving several quality-of-life domains simultaneously makes it an attractive complementary approach, but the evidence base needs strengthening.

Questions still open

Which specific cannabis formulations are most effective for cancer patients? How does medical cannabis interact with different chemotherapy regimens? Can medical cannabis be safely recommended as standard supportive care?

Common questions

Can medical cannabis help cancer patients feel better?

Multiple studies suggest yes — improvements in pain, sleep, appetite, mental health, and reduced nausea/vomiting have been reported. Some studies also found reduced opioid use. However, most evidence comes from non-randomized studies, and effects may vary by individual.

Is medical cannabis safe during cancer treatment?

Adverse effects in these studies were generally mild to moderate. However, the review noted potential interactions with some chemotherapy treatments, so cancer patients should always consult their oncology team before using medical cannabis.

Read the original research

Impact of Medical Cannabis on the Quality of Life of Cancer Patients: A Critical Review.

Journal of integrative and complementary medicine, 32(1), 18-26

View on PubMed ↗Publisher’s paper ↗

Citation

Correa, Larissa Gonçalves; Tucci, Adriana Marcassa. (2026). Impact of Medical Cannabis on the Quality of Life of Cancer Patients: A Critical Review.. Journal of integrative and complementary medicine, 32(1), 18-26. https://doi.org/10.1177/27683605251377417