Evidence Explorer · MS-N285 · Supportive care and drug interaction · Appraised November 9, 2026
In a placebo-controlled randomized trial, low-dose naltrexone did not improve fatigue or quality of life during radiation and temozolomide for high-grade glioma. Its opioid blockade is a major practical concern in cancer care.
Evidence at a glance
- Population: 110 people with high-grade glioma receiving concurrent radiation and temozolomide.
- Intervention: low-dose naltrexone 4.5 mg nightly (54 participants) versus placebo (56) for 16 weeks.
- Primary result: changes in brain-tumor quality of life and fatigue were not significantly different between groups.
- Evidence label: randomized negative evidence for fatigue and quality of life; cancer control was not tested.
What was studied
The double-blind trial began naltrexone on the first day of chemoradiation and continued through 16 weeks. Adverse-event patterns were similar and were attributed largely to temozolomide.
The study was not designed to test tumor response or survival. Reviews proposing anticancer mechanisms rely heavily on laboratory work and small or heterogeneous human reports.
What this evidence cannot establish
A tolerability finding does not demonstrate anticancer activity. This trial also does not address other diseases for which low-dose naltrexone is sometimes used off-label.
Safety and practical context
Naltrexone blocks opioid analgesics and is contraindicated in people currently receiving opioids or with opioid dependence. It can precipitate severe withdrawal and complicate urgent pain treatment.
After blockade ends, reduced opioid tolerance can increase overdose risk. Every oncologist, palliative-care clinician, surgeon and emergency clinician should know about current naltrexone use.
Questions for the care team
- Am I using any opioid pain medicine, cough medicine or antidiarrheal that could be blocked?
- What is the exact goal—fatigue relief, quality of life or an unsupported tumor claim?
- How would urgent surgery or escalating cancer pain be managed?
Sources and identifiers
- Randomized low-dose naltrexone glioma trial — PMID 35001215
- Trial registry — NCT01303835
- Current US naltrexone prescribing information
Funding and conflicts: The trial’s full funding and conflict disclosures were not independently re-extracted in this pass. The drug-label interaction warnings are regulatory safety information.
Source access and dates: Original reports, registry records and official safety sources available through the links above were checked November 9, 2026. Last literature search November 9, 2026.
Educational evidence summary, not individualized medical advice. Investigational or repurposed products should not replace established cancer treatment. Symptom, biomarker, laboratory or animal findings do not establish tumor control, recurrence prevention or longer survival.
