Avoid if known allergy/hypersensitivity to any constituents of Ganoderma lucidum or any member of its family. Skin reactivity to spore and whole body extracts have been reported. Hypersensitivity reactions to reishi and its derivatives may occur including dry mouth, nosebleed, nasal and throat dryness
Side Effects and Warnings
Acute and long-term studies have found Ganoderma lucidum to be generally well tolerated in recommended doses for up to 16 months. The most common adverse events reported are skin rash, dizziness and headache.
Use cautiously in patients who are taking diabetes/hypoglycemic drugs because reishi may lower blood sugar.
Low blood pressure may occur upon utilization of reishi and its derivatives.
Due to "blood thinning" capabilities, gastric bleeding could result from the use of reishi. Diarrhea and bloody stools may occur with supplemental doses. Mild gastrointestinal discomfort including nausea and diarrhea has been found in small percentage of cancer patients taking Ganoderma lucidum as Ganopoly®.
Reishi may prolong bleeding time and caution is advised in those patients with bleeding disorders (ulcers, hemophilia) or taking anticoagulants.
Pregnancy & Breastfeeding
Not recommended due to lack of sufficient data.
Adults (over 18 years old)
2-6 grams per day of reishi as raw fungus or an equivalent dosage of concentrated extract has been taken with meals. In clinical trials studying cancer, chronic hepatitis B, coronary heart disease, or diabetes, 600-1,800 milligrams has been taken three times daily. For high blood pressure, Linzhi extract (reishi) has been used in doses of 55 milligrams a day for four weeks. For pain management in herpes zoster, 36-72 grams of dry weight per day for up to ten days has been studied. Other doses used are 500-1,125 milligrams per day for treatment of proteinuria (excess protein in the urine), or 100 grams of reishi boiled in 600 milliliters water per dose for poisoning.
Children (under 18 years old)
Insufficient available evidence to recommend.
Interactions with Drugs
Reishi mushrooms are likely unsafe in patients with hemophilia due to its high adenosine content.
Reports have suggested that reishi may antagonize the effects of amphetamines.
Reishi therapy may increase or decrease the activity of certain antibiotics such as ampicillin, cefazolin, oxytetracycline and chloramphenical.
A study conducted on the antiherpetic activity of the acidic protein bound polysaccharide (APBP) that was isolated from capophores of Ganoderma lucidum had synergistic effects when administered with the prescription antiviral drug acyclovir.
Reishi and anticoagulants or NSAIDs may theoretically lead to additive effects or increased risk of bleeding. Reishi may cause bleeding due to prolongation of prothrombin time. Ganoderma lucidum inhibits platelet aggregation.
Ganoderma lucidum may cause additive blood pressure lowering effects.
Based on animal study, Ganoderma lucidum may cause an additive blood sugar lowering effect.
Reishi with HMG-CoA reductase inhibitor drugs ("statins") may result in additive effects.
Theoretically, use of reishi and protease inhibitors may result in additive effects.
Interactions with Herbs & Dietary Supplements
Reishi and anticoagulant herbs and supplements may theoretically lead to additive effects, increasing bleeding risk.
Ganoderma lucidum may cause additive blood pressure lowering effects with herbs and supplements such as fish oil, coenzyme Q10, and ginseng.
Ganoderma lucidum may cause additive blood sugar lowering effects with herbs and supplements such as beta-glucan, bitter melon, ginseng, gymnema, and chromium.
Theoretically, reishi may result in additive effects when taken with herbs and supplements like guggul, red rice yeast or garlic.