Evidence Explorer / Collection

Documented concerns

• St. John’s wort and irinotecan
• Acetyl-L-carnitine for taxane neuropathy
• Laetrile / amygdalin (“B17”)
• Vitamin B6 for hand–foot syndrome

Preparation and route matter

• IV vitamin C in pancreatic cancer
• Curcumin for radiation skin reactions
• Medicinal mushroom extracts
• American ginseng for fatigue

Nutrition and immune status matter

• Fasting around treatment
• Probiotics during pelvic radiation
• Hydration and electrolytes
• Omega-3s for weight loss

Supervision changes applicability

• Strength training with lymphedema
• Exercise with metastatic breast cancer
• Cooling gloves & socks
• Oral cryotherapy / ice chips

Bring the complete exposure list

Include prescription and over-the-counter medicines, vitamins, teas, powders, extracts, cannabis products and topical preparations. Bring the exact label, route, amount and frequency; an ingredient name alone is incomplete.

What the team needs to check

• Whether the product changes treatment exposure or adds bleeding, sedation or organ-toxicity risk.
• Whether kidney or liver function, blood counts, nutritional status or surgery changes suitability.
• Whether a studied preparation is comparable to the product being considered.
• What to monitor and when to stop, with a plan for new or worsening symptoms.

NCI: Cancer therapy interactions with foods and supplements · NCCIH: cancer and complementary approaches

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Added safety questions

• Coenzyme Q10: warfarin and insulin interactions; uncertain compatibility with some cancer treatments.
• Creatine: sparse oncology safety data; consider kidney function, hydration and combination-product ingredients.
• Topical diclofenac: NSAID allergy, kidney, bleeding and cardiovascular risk remain relevant despite lower systemic exposure.
• Acupuncture: bruising, blood counts, anticoagulants, infection and lymphedema precautions.
• Clinical hypnosis: low physical risk, but stop if the practice provokes distress; changing sweats still need medical evaluation.

Safety notes added October 14

• Soy foods after breast cancer: soy foods are not interchangeable with concentrated isoflavone supplements; review supplements separately.
• Selenium during pelvic radiotherapy: the trial used supervised high-dose sodium selenite only in documented deficiency; the NIH adult upper limit is 400 micrograms/day from all sources.
• Perioperative immunonutrition for gastrointestinal cancer surgery: “immunonutrition” is a specific combination formula, not a reason to assemble high-dose ingredients independently.
• Neutropenic diets during leukemia treatment and stem-cell transplant: liberalizing a neutropenic diet does not remove food-safety precautions for immunocompromised people.
• Photobiomodulation for oral mucositis: benefit and safety depend on a validated light protocol, treated field, hygiene and eye protection; consumer red-light devices are not equivalent.
• High-dose vitamin D with chemotherapy for metastatic colorectal cancer: high-dose vitamin D can cause hypercalcemia and kidney problems and did not improve cancer control in phase III.
• Self-acupressure for persistent fatigue after breast cancer: avoid broken or infected skin and areas with surgical or lymphedema precautions unless cleared; bruising can occur.
• Pomegranate products for prostate-cancer progression: extracts vary in composition; review glucose goals and medicines, and do not substitute pomegranate for surveillance or treatment.

Safety notes added October 15, 2026

• Black cohosh for hot flashes after breast cancer: rare serious liver-injury reports, uncertain safety after hormone-sensitive cancers and mislabeled products are important cautions.
• Guarana for cancer-related fatigue: caffeine and other stimulants can worsen insomnia, anxiety, palpitations or blood pressure.
• Chamomile mouthwash for treatment-related oral mucositis: chamomile can trigger severe allergy, particularly with ragweed-family allergy, and has reported warfarin interactions.
• Calendula ointment for breast-radiotherapy skin reactions: calendula can cause contact allergy and should follow the radiation clinic’s product and timing rules.
• Aloe vera gel for radiation dermatitis: topical aloe is distinct from oral aloe latex or whole-leaf products; stop for burning, rash or allergy.
• Vitamin E for hot flashes after breast cancer: high-dose vitamin E can increase bleeding risk, especially with anticoagulants, antiplatelet drugs or surgery.
• Intravenous glutathione to prevent platinum neuropathy: intravenous glutathione is an investigational medical infusion, not an oral supplement or unregulated wellness-clinic product.
• Oral L-glutamine for treatment-related oral mucositis: oral glutamine findings are regimen-specific; kidney/liver function, product purity and total nutrition plan matter.
• Milk thistle for chemotherapy-associated liver injury: milk-thistle products can be mislabeled or contaminated and may interact with liver-metabolized medicines.
• Goshajinkigan to prevent oxaliplatin neuropathy: the phase III formula increased rather than prevented neuropathy; avoid for this purpose outside research.

Exercise and rehabilitation safety — October 16, 2026

• Postoperative shoulder rehabilitation: time mobility and strengthening around the operation, wound healing, drains, pain and range of motion.
• Head-and-neck prehabilitation: coordinate exercise with nutrition, anemia, airway symptoms and treatment timing; do not delay chemoradiotherapy.
• Exercise during neoadjuvant chemotherapy: adapt for infection, blood counts, cardiotoxic therapy, neuropathy and day-to-day symptoms.
• Exercise with bone metastases: prescription must be lesion-aware; sudden focal pain or neurologic change requires urgent assessment.
• Exercise for cognitive symptoms: new focal neurologic symptoms or rapid decline require medical evaluation.
• Exercise with neuropathy: balance, footwear, sensation and falls can change which aerobic activity is safe.
• Manual lymph drainage: new swelling, warmth, fever, pain or breathlessness should be assessed for infection or thrombosis before massage.
• Swallowing exercises: coughing, choking, recurrent chest infection, dehydration or inability to maintain intake needs prompt review.
• Exercise during allogeneic transplant: daily limits depend on infection, anemia, thrombocytopenia, graft-versus-host disease, lines and falls.
• Exercise for insomnia: timing and intensity need adaptation; persistent insomnia still requires evaluation and access to CBT-I where appropriate.

Mind–body and sleep safety notes — October 17, 2026

• Acupuncture: discuss thrombocytopenia, neutropenia, anticoagulation, lymphedema risk, fragile skin, infection risk and implanted devices; use a licensed oncology-aware practitioner.
• Tai chi and yoga: adapt for neuropathy, dizziness, recent surgery, radiation dermatitis, lymphedema, cardiopulmonary limits and bone metastases.
• Bright light: device intensity and timing matter; eye disease, photosensitizing medicines, migraine and bipolar-spectrum illness warrant clinician input.
• Mindfulness, imagery, expressive writing, dignity and meaning-centered work: difficult emotions can surface. Severe depression, trauma symptoms, psychosis, delirium or suicidal thinking need direct clinical care.
• Persistent fatigue or insomnia: supportive practices do not replace evaluation for anemia, infection, endocrine problems, medication effects, pain, sleep apnea, depression or disease progression.

Safety additions · October 18, 2026

• Needling: bruising, bleeding, infection and fainting; extra caution with low platelets or neutrophils, anticoagulation, compromised skin, bone lesions, indwelling devices and lymphedema risk.
• Electroacupuncture: review implanted electrical devices and cardiac history before use.
• Foot pressure/reflexology: avoid wounds, infection, painful neuropathy, suspected fracture and known or suspected deep-vein thrombosis.
• Oral cryotherapy: regimen- and timing-specific; cold-sensitive dental disease, aspiration risk, Raynaud phenomenon and cryoglobulinemia may make it unsuitable.
• Scalp or limb cooling: cold pain, headache, skin injury and rare frostbite; use controlled oncology-center protocols, not improvised freezing.
• P6 wristbands: remove with numbness, swelling, skin breakdown or color change; consider neuropathy, edema, vascular disease and IV placement.

These precautions are practical boundaries, not proof that an intervention works.