Reishi Mushroom

• Immune modulation and adjuvant oncology support: Research suggests reishi may enhance aspects of immune function (e.g., natural killer cell activity, lymphocyte subsets) and modestly improve quality of life and functional status when used alongside standard cancer care. Evidence is based on small randomized trials and systematic reviews; effects on hard outcomes (tumor response, survival) are unproven and evidence is mixed. Evidence strength: moderate for immune markers/QoL; emerging for clinical endpoints.
• Stress, fatigue, and sleep: Traditionally used to calm the spirit (shen) and support resilience. Some small randomized trials report modest reductions in fatigue and improvements in sleep quality in conditions like neurasthenia or cancer-related fatigue, but studies are heterogeneous. Evidence strength: emerging.
• Cardiometabolic markers: Findings are inconsistent for lowering fasting glucose, HbA1c, blood pressure, or LDL cholesterol; some studies show small improvements while others show no benefit. Evidence strength: emerging/mixed.
• Inflammation/antioxidant status: Limited human data suggest small improvements in inflammatory or oxidative stress biomarkers; clinical significance is uncertain. Evidence strength: emerging. Note: Reishi should not replace conventional medical treatments, particularly for cancer; any use as an adjunct should be coordinated with a clinician.

Common (usually mild, dose-related): gastrointestinal upset (nausea, diarrhea, abdominal discomfort), dry mouth or throat, dizziness, headache, skin itching or rash. Less common: nasal bleeding, mouth/throat irritation from powders, blood pressure changes (usually lowering), fatigue or sedation. Rare but serious: liver injury (idiosyncratic hepatotoxicity reported, especially with spore powders or high-dose extracts), clinically significant bleeding (particularly with concurrent anticoagulants/antiplatelets), allergic reactions (including to spores). Frequency estimates vary; serious events are rare but documented in case reports. Higher doses and alcohol-based extracts may increase adverse event risk.

Commonly used ranges in studies (forms vary by preparation and standardization):

• Dried fruiting body (powder/tea): about 1.5–9 g per day, often divided.
• Standardized extracts (polysaccharide- or triterpene-rich): roughly 1–3 g per day (standardizations vary, e.g., ~10–20% polysaccharides or specified triterpenes).
• Spore powder: about 1–3 g per day; spore oil typically used in smaller amounts per manufacturer standards. Durations in clinical trials commonly range from 4–16 weeks. Optimal dose depends on extract composition, individual factors, and indication; higher doses may increase adverse effects.

• Bleeding risk: Active bleeding disorders (e.g., hemophilia, thrombocytopenia) or concurrent use of anticoagulants/antiplatelets due to potential antiplatelet effects.
• Pre-/post-surgery: Discontinue at least 2 weeks before elective surgery to minimize bleeding risk and hemodynamic instability.
• Pregnancy and breastfeeding: Insufficient reliable safety data—avoid unless specifically advised by a clinician.
• Autoimmune disease or organ transplant: Immunomodulatory effects may exacerbate autoimmune activity or reduce effectiveness of immunosuppressants (e.g., tacrolimus, cyclosporine). Use only with specialist guidance.
• Hypotension or on antihypertensives: May have additive blood pressure–lowering effects; monitor closely if used.
• Diabetes or on glucose-lowering therapy: Potential additive glucose-lowering—monitor for hypoglycemia and adjust therapy with clinician oversight.
• Liver disease or prior herb-induced liver injury: Use cautiously or avoid; monitor liver enzymes if used.
• Mushroom allergy or asthma sensitive to spores: Risk of allergic reactions; avoid, especially spore products.