Mistletoe
Also called: Viscum album, Iscador, Helixor.
Last reviewed 2026-09-16. How this works.
Quality of life Grade C
Human evidence exists and does not settle it.
Mistletoe may help people feel better, and it did not change whether the cancer came back.
A randomised quality-of-life signal. No difference in recurrence or mortality.
The claim
The claim, made for mistletoe since it was first proposed as a cancer treatment in 1920, is that injected extracts of the plant treat cancer and help people tolerate treatment.1
What it does
Extracts contain lectins and viscotoxins with effects on immune cells. The book grades the quality-of-life claim rather than the tumour claim, because that is where the randomised signal is.
The evidence
A meta-analysis of randomised trials around the time of cancer surgery found no difference between mistletoe extract and no added therapy for mortality, or for recurrence. Both intervals sit squarely across one.2
Two randomised trials in that analysis did report beneficial effects on natural killer cells in bowel cancer, and one reported an improvement in quality of life. That is the basis of this grade, and it is a modest one.2
Larger survival figures circulate from real-world lung cancer data. They are non-randomised, and the chapter note records that they come from reviews written from inside the mistletoe research field and have not been read in the original. They are not used here.3
The studies this rests on
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Pooled randomised trials of mistletoe extracts around cancer surgery2
A meta-analysis, summarising randomised trials, measured what patients reported.
no difference in mortality or recurrence; quality-of-life improvement reported in one trial and immune cell effects in two.
risk ratio 1, interval 0.79 to 1.27. mortality; recurrence 1.03, interval 0.79 to 1.33
What is absent
The randomised evidence shows no effect on mortality and no effect on recurrence. This grade covers quality of life only, and the difference between those two claims is the whole entry.
Scope: survival or recurrence.
Established by published review, Current Oncology 2023;30(9):595, checked 2026-09-16. Result: no difference for mortality, risk ratio 1.00, or for recurrence, risk ratio 1.03.2
What to ask
Is mistletoe something that would interfere with my treatment if I were having it?
The dish-to-person gap
The register holds no human pharmacokinetic measurement for mistletoe extract against any laboratory concentration.
When to call your team — no warning signs are recorded
Whatever you are taking or thinking of taking, the people treating you can only weigh it if they know about it. That is true when nothing has been written down here, and it is most true then.
The register records no warning signs for mistletoe extract. That is not a statement that nothing can go wrong.
Interactions
The register holds no measured interaction between mistletoe extract and a cancer treatment class. An empty list means nobody has measured it.
Nobody having looked is not the same as nothing being there. That is what this line says and all it says.
The whole interaction list, and how to turn it into a pharmacy review request.
Find a trial instead
Quality of life is a legitimate endpoint and one a trial can measure.
Search ClinicalTrials.gov for recruiting studies of mistletoe OR Viscum album
A trial is the same decision with monitoring, a known preparation and a doctor who knows what else you are taking.
References
The application of mistletoe in cancer, recorded as first proposed by Rudolf Steiner in 1920, as described in current reviews of mistletoe in oncology.
No persistent identifier recorded.
How this was reached: transcribed from chapter note, via docs/CHAPTER-NOTES.json, chapter 18 note 1.
Mistletoe extracts during the oncological perioperative period: a systematic review and meta-analysis of human randomized controlled trials. Current Oncology 2023;30(9):595.
How this was reached: transcribed from chapter note, via docs/CHAPTER-NOTES.json, chapter 18 note 2.
Real-world lung cancer figures as described in recent reviews written from within the mistletoe research field.
No persistent identifier recorded.
How this was reached: transcribed from chapter note, via docs/CHAPTER-NOTES.json, chapter 18 note 3.