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Botanical Name: Ganoderma lucidum (W. Curtis.: Fr.) P. Karst.
Pharmacopoeial Name: Fructus ganodermi.
Synonym: Boletus lucidus Fr.
Common Names: Reishi, reishi mushroom, red reishi; Ling Zhi. ( Ganoderma japonicum = black reishi; Ganoderma applanatum = artist’s conk).

Summary Table
herb description


Ganodermataceae (Polyporaceae).

Related Species

Ganoderma japonicum (Fr.) Lloyd. (synonym, G. sinense Zhao, Xu et Zhang.), Ganoderma applanatum (Pers.) Pat, Ganoderma tsugae Murrill.

Habitat and Cultivation

A woody shelf-fungus that grows on rotting tree stumps and fallen logs in temperate forests throughout much of North America, most of Europe, South America and Asia, typically affecting oak trees. Reishi is now rare in the wild in China and rarer in Japan but has been under widespread industrial-scale cultivation in China for several years, which constitutes the bulk of commercial reishi supply internationally.

Parts Used

Fruiting body. Spore and mycelium preparations exist but have limited commercial availability; they are not identical to the fruiting body in composition or activity.

Common Forms

Dried whole fruiting body, by decoction (or very finely powdered).

  • Tincture:   Traditionally, rice wine extract.

  • Standardized Solid Extract:   Concentrates available greater than 20:1.

interactions review

Strategic Considerations

Traditional Chinese use of reishi includes stand-alone herb for various conditions (Chinese syndrome-patterns), including heart (Xin) qi and lung (Fei) qi deficiencies. 1 In modern Western usage, reishi is primarily considered as a safe and virtually nontoxic immunomodulatory agent. It is primarily used in the clinical context of immunocompromise, such as chronic fatigue immune dysfunction syndrome (CFIDS), or as an adjunct in integrative cancer protocols to support patients undergoing myelosuppressive conventional therapies. Pharmacological data suggest four primary areas of activity for reishi extracts: immune enhancing and antitumorigenic, cardiovascular regulatory, hypoglycemic, and hepatoprotective. 2 Of these, interactions with pharmaceuticals are suggested primarily by the immunomodulatory data.

Support for use of reishi in oncological settings is largely derived from experimental studies on the biological activities of its polysaccharide and triterpene compounds. These have direct antitumor activity mediated by several pathways, notably the inhibition of the key transcription factors nuclear factor-kappa B (NF-κB) and activating protein 1 (AP-1). The indirect anticancer effects are mediated by promotion of mixed-lymphocyte responses, including enhancement of cytotoxic activity of monocyte-macrophages, natural killer (NK) cells, and lymphokine-activated killer (LAK) cells and increased secretion of cytokines such as interleukin-1 (IL-1), IL-6, and interferon gamma (IFN-γ). 3-5Protection against myelosuppression from chemotherapeutic agents and radiation therapy has moderate experimental and anecdotal clinical support; however, clinical trials are required to establish the efficacy of reishi for this purpose. Although some sources have cited Chinese-language clinical studies in support of these uses, full translations are unavailable, and evaluation of these trials by these secondary sources is typically schematic. 6

More substantial clinical data are available for related mushrooms, such as Coriolus, Polyporus, and Lentinus, and medicinal mushroom polysaccharides, particularly the branched (1→3)-beta-Dglucans, are thought to be broadly similar in their general immunomodulatory and anticancer effects. 7,8Additive interactions with antimicrobial pharmaceutical agents have been reported (see later), but these probably are also indirect results from a general enhancement of cell-mediated immunity and antiviral activity by reishi compounds, rather than specific herb-drug interactions. The long-term use of immunomodulating herbs in patient populations dependent on immunosuppressive therapies (e.g., to prevent graft rejection) is de facto contraindicated, and reishi extracts have been shown to reverse immunosuppressive effects of morphine. 9

Cardiovascular drug interactions seem unlikely given the mild cardiotonic effects of reishi despite suggestions in secondary literature of possible potentiating interactions with cholesterol-lowering and anticoagulant drugs. These interactions have not been demonstrated or reported, and claims of their likelihood are classified as “speculative” here, along with equally hypothetical suggestion of interactions with hypoglycemic drugs, as discussed later.

Effects on Drug Metabolism and Bioavailability

Pharmacokinetic interactions between reishi and pharmaceutical drugs have not been reported, and studies on the effects of the herb on drug-metabolizing systems have not been conducted to date. Induction of human hepatic glutathione- S-transferase in vitro by reishi polysaccharide has been recorded in one in vitro study. 10 Inhibition of beta-glucuronidase in vitro by the triterpene constituent ganoderenic acid A was demonstrated in vitro, and the same constituent had a potent inhibitory effect against carbon tetrachloride (CCl4)–induced hepatotoxicity in a rodent model. 11

The hepatoprotective effects of the herb may counter solvent and other chemical or solvent-induced hepatotoxicity. 12,13These effects on drug-metabolizing enzymes may contribute, along with the antioxidant effects of the herb, to the established hepatoprotective properties of reishi observed in some studies. From these limited data, the potential theoretically exists for some modulation of clearance of glucuronide prodrugs, as well as accelerated clearance of glutathione and glucuronated drug conjugates. The effects of variation in activity of beta-glucuronidase on drug metabolism have not been systematically studied to date, but it may be a clinically significant determinant of variability of individual response to pharmaceuticals. 14

herb-drug interactions
Antimicrobial and Antiviral Therapies
Antineoplastic Therapies, Including Anthracyclines, Radiotherapy, and Surgery
  • Evidence: Cyclophosphamide (Cytoxan, Endoxana, Neosar, Procytox), doxorubicin (Adriamycin, Rubex).
  • Extrapolated, based on similar properties: Daunorubicin (Cerubidine, DaunoXome), epirubicin (Ellence, Pharmorubicin), idarubicin (Idamycin, Zavedos), mitoxantrone (Novantrone, Onkotrone).
Potential or Theoretical Beneficial or Supportive Interaction, with Professional Management
Prevention or Reduction of Drug Adverse Effect

Probability: 4. Plausible
Evidence Base: Preliminary

Effect and Mechanism of Action

Reishi extracts may protect against immunosuppressive aspects of antineoplastic therapies and improve therapeutic outcomes. Mechanisms are multifactorial and include protection against specific toxicities, reversal of leukopenia, and preservation of cell-mediated immune responses; antioxidant scavenging of free radicals; inherent anticancer activity resulting from inhibition of transcription factors NF-κB, AP-1, and free-radical reactive oxygen species (ROS); and other mechanisms.


Reishi (Ganoderma japonicum)increased white blood cell (WBC) count in 72.5% of 175 leukopenic patients, according to a Chinese study cited by Chen and Chen. 6 A Chinese rodent study of doxorubicin (Adriamycin) toxicity by Hongwei and colleagues, cited in detail by Upton, 2 found that oral pretreatment with reishi extract at 500 mg/kg body weight for 14 days significantly reduced histological parameters of doxorubicin-induced toxicity in cardiac, hepatic, and renal cells, compared with controls receiving doxorubicin alone. An unrelated study demonstrated dose-dependent cardioprotective activity of hot-water reishi extracts against ethanol-induced heart toxicity in rodents through antioxidative protection against lipid peroxidation. 24 This is the established mechanism of anthracycline-induced cardiotoxicity. Lu and Lin 9 demonstrated reversal of B-cell and T-cell response suppression by morphine after administration of a polysaccharide reishi extract to morphine-dependent mice. Animal studies have demonstrated radioprotective effects of reishi in recovering immunocompetence after radiation exposure. 25,26 However, this includes protection against deoxyribonucleic acid (DNA) strand breakage. 27 A murine model showed that oral pretreatment with reishi enabled a significant reduction in cyclophosphamide toxicity in terms of preventing leukopenia. An in vitro study found that reishi may inhibit the angiogenic vascular endothelial growth factor (VEGF), and theoretically, angiogenesis inhibition may interfere with postsurgical wound repair. 28

McKenna et al. 29 reviewed two small human studies from conference reports relating to Ganodermause in a clinical oncology setting. The first, an open-label trial by Kupin 30 of 48 patients with advanced cancer (renal, gastric, breast), examined the effects of coadminstering reishi extracts during chemotherapy and radiation. The WBC levels were normalized in those taking reishi compared with controls, and treatment-induced leukopenia was rapidly ameliorated in the reishi group, who also had greater appetite and higher levels of general vigor than the controls. Of those patients requiring surgery, the reishi subjects experienced faster recovery and improved wound healing compared with the control group surgical candidates. A smaller study of patients with acute myelogenous leukemia (AML) or nasopharyngeal carcinoma who were pretreated with reishi extracts for 1 week before chemo/radiotherapy, contining the extracts for 3 months after the treatments, reported similar findings in terms of increased efficacy of treatment and reduction of treatment-induced adverse effects. 31

Clinical Implications and Integrative Therapeutics

The pluripotent anticancer effects of reishi polysaccharides and triterpenes have been subject of extensive experimental study, but to date, clinical trials have not confirmed these in vivo. Evidence for other mushroom beta-glycans is perhaps more compelling, but reasonable rationale appears to exist for combining reishi extracts into protocols designed for therapeutic protection against myelosuppression as a dose-limiting toxicity of chemotherapy. If the antiangiogenic effects of reishi are confirmed, combination with monoclonal antibody drugs targeting VEGF is theoretically a reasonable strategy.

theoretical, speculative, and preliminary interactions research, including overstated interactions claims
Anticoagulants, Oral Vitamin K Antagonists
Central Stimulants; Chlorpromazine, Phenobarbital, Reserpine
HMG-CoA Reductase Inhibitors (Statins) and Other Cholesterol-Lowering Drugs
Insulin and Oral Hypoglycemic Agents
  • 1.Bensky D, Clavey S, Stogër E, Gamble A. Ling Zhi. Chinese Herbal Medicine: Materia Medica. 3rd ed. Seattle: Eastland Press; 2004:933-935.
  • 2.Upton R. Reishi mushroom Ganoderma lucidum. Santa Cruz, Calif: American Herbal Pharmacopoeia; 2000.
  • 3.Sliva D. Ganoderma lucidum (reishi) in cancer treatment. Integr Cancer Ther 2003;2:358-364.View Abstract
  • 4.Lin YL, Liang YC, Lee SS, Chiang BL. Polysaccharide purified from Ganoderma lucidum induced activation and maturation of human monocyte-derived dendritic cells by the NF-κB and p38 mitogen-activated protein kinase pathways. J Leukoc Biol 2005;78:533-543.View Abstract
  • 5.Kuo MC, Weng CY, Ha CL, Wu MJ. Ganoderma lucidum mycelia enhance innate immunity by activating NF-κB. J Ethnopharmacol 2005;103:217-222.View Abstract
  • 6.Chen J, Chen T. Ling Zhi (Ganoderma). Chinese Medical Herbology and Pharmacology. City of Industry, Calif: Art of Medicine Press Inc; 2004:770-771.
  • 7.Wasser SP. Medicinal mushrooms as a source of antitumor and immunomodulating polysaccharides. Appl Microbiol Biotechnol 2002;60:258-274.View Abstract
  • 8.Hobbs C. Medicinal Mushrooms: an Exploration of Tradition, Healing, & Culture. 3rd ed. Loveland, Colo: Interweave Press; 1996.
  • 9.Lu Z, Lin Z. Antagonistic effect of Ganoderma polysaccharides peptide against immunosuppression caused by repetitive in vivo treatments of morphine. International Symposium on Ganoderma Research. Program and Abstracts vol. Beijing: Beijing Medical University; 1994:82.
  • 10.Kim HS, Kacew S, Lee BM. In vitro chemopreventive effects of plant polysaccharides (Aloe barbadensis Miller, Lentinus edodes, Ganoderma lucidum and Coriolus versicolor). Carcinogenesis 1999;20:1637-1640.View Abstract
  • 11.Kim DH, Shim SB, Kim NJ, Jang IS. Beta-glucuronidase-inhibitory activity and hepatoprotective effect of Ganoderma lucidum. Biol Pharm Bull 1999;22:162-164.View Abstract
  • 12.Lin WC, Lin WL. Ameliorative effect of Ganoderma lucidum on carbon tetrachloride–induced liver fibrosis in rats. World J Gastroenterol 2006;12:265-270.View Abstract
  • 13.Yang XJ, Liu J, Ye LB et al. In vitro and in vivo protective effects of proteoglycan isolated from mycelia of Ganoderma lucidum on carbon tetrachloride–induced liver injury. World J Gastroenterol 2006;12:1379-1385.View Abstract
  • 14.Sperker B, Backman JT, Kroemer HK. The role of beta-glucuronidase in drug disposition and drug targeting in humans. Clin Pharmacokinet 1997;33:18-31.View Abstract
  • 15.Yoon SY, Eo SK, Kim YS et al. Antimicrobial activity of Ganoderma lucidum extract alone and in combination with some antibiotics. Arch Pharm Res 1994;17:438-442.View Abstract
  • 16.Oh KW, Lee CK, Kim YS et al. Antiherpetic activities of acidic protein bound polysacchride isolated from Ganoderma lucidum alone and in combinations with acyclovir and vidarabine. J Ethnopharmacol 2000;72:221-227.View Abstract
  • 17.Eel-Mekkawy S, Meselhy MR, Nakamura N et al. Anti-HIV-1 and anti-HIV-1-protease substances from Ganoderma lucidum. Phytochemistry 1998;49:1651-1657.
  • 18.Eo SK, Kim YS, Lee CK, Han SS. Antiviral activities of various water and methanol soluble substances isolated from Ganoderma lucidum. J Ethnopharmacol 1999;68:129-136.
  • 19.Eo SK, Kim YS, Lee CK, Han SS. Possible mode of antiviral activity of acidic protein-bound polysaccharide isolated from Ganoderma lucidum on herpes simplex viruses. J Ethnopharmacol 2000;72:475-481.View Abstract
  • 20.Kohguchi M, Kunikata T, Watanabe H et al. Immuno-potentiating effects of the antler-shaped fruiting body of Ganoderma lucidum (Rokkaku-Reishi). Biosci Biotechnol Biochem 2004;68:881-887.View Abstract
  • 21.Wang SY, Hsu ML, Hsu HC et al. The anti-tumor effect of Ganoderma lucidum is mediated by cytokines released from activated macrophages and T lymphocytes. Int J Cancer 1997;70:699-705.View Abstract
  • 22.Gao Y, Zhou S, Jiang W et al. Effects of ganopoly (a Ganoderma lucidum polysaccharide extract) on the immune functions in advanced-stage cancer patients. Immunol Invest 2003;32:201-215.View Abstract
  • 23.Hijikata Y, Yamada S. Effect of Ganoderma lucidum on postherpetic neuralgia. Am J Chin Med 1998;26:375-381.View Abstract
  • 24.Wong KL, Chao HH, Chan P et al. Antioxidant activity of Ganoderma lucidum in acute ethanol-induced heart toxicity. Phytother Res 2004;18:1024-1026.View Abstract
  • 25.Chen WC, Hau DM, Lee SS. Effects of Ganoderma lucidum and krestin on cellular immunocompetence in gamma-ray-irradiated mice. Am J Chin Med 1995;23:71-80.View Abstract
  • 26.Kubo N, Myojin Y, Shimamoto F et al. Protective effects of a water-soluble extract from cultured medium of Ganoderma lucidum (Rei-shi) mycelia and Agaricus blazei murill against X-irradiation in B6C3F1 mice: increased small intestinal crypt survival and prolongation of average time to animal death. Int J Mol Med 2005;15:401-406.
  • 27.Kim KC, Kim IG. Ganoderma lucidum extract protects DNA from strand breakage caused by hydroxyl radical and UV irradiation. Int J Mol Med 1999;4:273-277.View Abstract
  • 28.Cao QZ, Lin ZB. Ganoderma lucidum polysaccharides peptide inhibits the growth of vascular endothelial cell and the induction of VEGF in human lung cancer cell. Life Sci 2006;78:1457-1463.View Abstract
  • 29.McKenna D, Jones K, Hughes K, Humphrey S. Reishi. Botanical Medicines. 2nd ed. Binghamton, NY: Haworth Press; 2002:825-851.
  • 30.Kupin V. A new biological response modifier—Ganoderma lucidum—and its application in oncology. The 4th International Symposium on Ganoderma lucidum. Seoul, Korea: Seoul National University; 1992:36-39.
  • 31.Teow S. The therapeutic value of Ganoderma lucidum. In: Buchanan P, Heu R, Moncalvo J, eds. Ganoderma: systematics, phytopathology and pharmacology. Proceedings of Contributed Symposium 59 A, B, 5th International Mycological Congress. Taipei, Taiwan, Republic of China; 1995:105-113.
  • 32.Shimizu A, Yano T, Saito Y, Inada Y. Isolation of an inhibitor of platelet aggregation from a fungus, Ganoderma lucidum. Chem Pharm Bull (Tokyo) 1985;33:3012-3015.View Abstract
  • 33.Su CY, Shiao MS, Wang CT. Differential effects of ganodermic acid S on the thromboxane A2–signaling pathways in human platelets. Biochem Pharmacol 1999;58:587-595.View Abstract
  • 34.Su C, Shiao M, Wang C. Potentiation of ganodermic acid S on prostaglandin E(1)-induced cyclic AMP elevation in human platelets. Thromb Res 2000;99:135-145.View Abstract
  • 35.Tao J, Feng KY. Experimental and clinical studies on inhibitory effect of Ganoderma lucidum on platelet aggregation. J Tongji Med Univ 1990;10:240-243.View Abstract
  • 36.Kwok Y, Ng KFJ, Li CCF et al. A prospective, randomized, double-blind, placebo-controlled study of the platelet and global hemostatic effects of Ganoderma lucidum (Ling-Zhi) in healthy volunteers. Anesth Analg 2005;101:423-426, table of contents.
  • 37.Berger A, Rein D, Kratky E et al. Cholesterol-lowering properties of Ganoderma lucidum in vitro, ex vivo, and in hamsters and minipigs. Lipids Health Dis 2004;3:2.View Abstract
  • 38.Shiao MS. Natural products of the medicinal fungus Ganoderma lucidum: occurrence, biological activities, and pharmacological functions. Chem Rec 2003;3:172-180.View Abstract
  • 39.Hikino H, Konno C, Mirin Y, Hayashi T. Isolation and hypoglycemic activity of ganoderans A and B, glycans of Ganoderma lucidum fruit bodies. Planta Med 1985:339-340.View Abstract
  • 40.Hikino H, Ishiyama M, Suzuki Y, Konno C. Mechanisms of hypoglycemic activity of ganoderan B: a glycan of Ganoderma lucidum fruit bodies. Planta Med 1989;55:423-428.View Abstract
  • 41.Zhang HN, Lin ZB. Hypoglycemic effect of Ganoderma lucidum polysaccharides. Acta Pharmacol Sin 2004;25:191-195.View Abstract