Turkey Tail
Turkey tail (Trametes versicolor) in plain language: how the Japanese cancer-care drug PSK differs from supplements, what trials found, and why the oncology team must know.
Content last updated . This page has not been medically reviewed.
Safety first. Supplements can cause side effects and interact with medicines. Read mushroom safety and interactions before you use any mushroom product.
Cancer care comes first. A supplement is not a cancer treatment. If you are in cancer care, tell your oncology team about any turkey tail product before you start, because they know your treatment plan. The US Food and Drug Administration (FDA) has not approved coriolus extracts as additional cancer treatments, according to Memorial Sloan Kettering Cancer Center (MSK). [1] MSK also advises people who are pregnant or breastfeeding to avoid coriolus until safety data are available. [1] See Turkey tail, PSK and cancer care and what to tell your care team.
What it is
Turkey tail is Trametes versicolor (L.) Lloyd, the accepted name; the older name Coriolus versicolor is a synonym, and both appear on labels and in studies. [2] The National Cancer Institute (NCI) summary describes it as a woody bracket fungus that grows on dead logs worldwide, called Yun Zhi in traditional Chinese medicine and Kawaratake in Japan, and says that many other Trametes species are difficult to distinguish from it. [3] That is why this guide gives no identification help: wild mushrooms should never be eaten on the strength of a description or photo. For any wild mushroom that was eaten, call Poison Help at 1-800-222-1222 in the US.PSK is a medicine in Japan; supplements are different
- PSK (krestin) is a proprietary extract. NCI says a purified hot water extract of cultivated mycelium has been used in Japan as an adjunct in cancer treatment, that PSK is an approved mushroom product there, has been used since the mid-1970s, and has a well-established safety record with few adverse events reported. [3]
- PSP is another extract from T. versicolor, produced in China. [3]
- Supplements in other countries are different products. MSK says many over-the-counter products are not standardized and that it is unclear whether PSK, PSP and other extracts have comparable effects. [1]
Do not assume a capsule matches the product tested in a trial. See PSK, PSP and lentinan.
Traditional use
Traditional use only, not proof. The NCI summary says the fungus has been used in traditional Chinese medicine for many years to treat pulmonary diseases. [3] MSK adds that it is used in traditional Chinese medicine as a tonic. [1]What research shows
| Question | What the source found | Strength of evidence | Form and population |
|---|---|---|---|
| Side effects of chemotherapy in colorectal cancer | A Cochrane review (2022) of 7 trials (1,569 people) was uncertain about the effect on side effects; certainty was very low. [4] | Insufficient evidence | PSK extract, mostly in Japan |
| Survival in colorectal cancer | The same review found low-certainty evidence of a small effect on 5-year survival (relative risk 1.08), and noted the chemotherapy regimens used do not reflect current preferred practice. [4] | Promising but limited | PSK extract after surgery, with chemotherapy |
| Gastrointestinal cancers | A 2017 network meta-analysis of 23 trials (10,684 people) reported improved overall survival with PSK, most clearly in colorectal and gastric cancer and with chemotherapy. [5] | Promising but limited; trial quality varies | PSK as an adjunct to treatment |
| Immune markers in breast cancer | A phase 1 trial (11 people enrolled) tested 3, 6 and 9 g a day for 6 weeks after radiotherapy and reported tolerability and trends in some immune cells. [6] | Biomarker only; a safety study, not a treatment test | Turkey tail preparation, women after breast cancer treatment |
| Gut bacteria | In 24 healthy volunteers, PSP produced consistent gut microbiome changes that the authors describe as prebiotic-like. [7] | Biomarker only | PSP, healthy adults |
| General health claims, such as colds or energy | Proper evidence not found. We searched PubMed for human trials of Trametes versicolor and found trials in cancer care and the microbiome study above, none on colds or energy. | Insufficient evidence | Not applicable |
A 2023 systematic review of mushroom studies in cancer care, which included 39 clinical studies, concluded the evidence is inconclusive for recommending routine use; many studies were small or observational. [8]
Official statements
- NCI (PDQ, updated 2024): PSK is approved for cancer treatment in Japan; the FDA has not approved medicinal mushrooms to treat cancer or any other condition. [3]
- MSK: the FDA has not approved coriolus extracts as additional cancer treatments. [1]
Frequently asked questions
Is turkey tail the same as PSK?
No. PSK is a proprietary extract approved for cancer treatment in Japan; supplements are different products. [3][1]
Can turkey tail cure cancer?
No. The evidence concerns adjunct use alongside standard treatment, and a Cochrane review rated it low or very low certainty. [4]
Is turkey tail safe during chemotherapy?
That is for your oncology team to decide. A small trial of up to 9 g a day in breast cancer survivors reported it was tolerable. [6]
Is Trametes versicolor the same as Coriolus versicolor?
Yes. Coriolus versicolor is a listed synonym. [2]
Does turkey tail help gut health?
One small trial of PSP found prebiotic-like changes in gut bacteria, which is not a health outcome. [7] See mushrooms and gut health.
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Safety in more detail
- Side effects: MSK lists dark-colored stools and darkening of fingernails as rare effects, and says low-grade blood and digestive effects seen with chemotherapy may be caused by the chemotherapy itself. [1]
- Medicines: we did not find drug-interaction statements for turkey tail in the sources we read. That is not proof of safety. Ask a pharmacist; see medicine interactions and turkey tail safety and side effects.
- Pregnancy and breastfeeding: avoid until safety data exist, per MSK. [1] See pregnancy and breastfeeding.
- Children, liver, kidney, allergy, bleeding: not described in the sources we read.
- Quality: the NCI summary says supplement ingredients can vary from lot to lot. [3] See quality testing and certifications.
References
- Memorial Sloan Kettering Cancer Center, Coriolus versicolor, About Herbs Read 2026-10-23.
- GBIF Backbone Taxonomy, Trametes versicolor (L.) Lloyd Read 2026-10-23.
- National Cancer Institute, Medicinal Mushrooms (PDQ), Health Professional Version, updated November 6, 2024 Read 2026-10-23.
- Pilkington K et al. Coriolus (Trametes) versicolor mushroom to reduce adverse effects from chemotherapy or radiotherapy in people with colorectal cancer. Cochrane Database Syst Rev 2022 Read 2026-10-23.
- Can polysaccharide K improve therapeutic efficacy and safety in gastrointestinal cancer? A systematic review and network meta-analysis. Oncotarget 2017 Read 2026-10-23.
- Torkelson CJ et al. Phase 1 Clinical Trial of Trametes versicolor in Women with Breast Cancer. ISRN Oncol 2012 Read 2026-10-23.
- Effects of polysaccharopeptide from Trametes versicolor and amoxicillin on the gut microbiome of healthy volunteers: a randomized clinical trial. Gut Microbes 2014 Read 2026-10-23.
- Medicinal Mushroom Supplements in Cancer: A Systematic Review of Clinical Studies. Curr Oncol Rep 2023 Read 2026-10-23.