Comprehensive NCI PDQ summary covering history, mechanism, human studies, adverse effects, drug interactions, and current clinical trials. Notes FDA has not approved high-dose IV vitamin C as a cancer treatment.
High-Dose Vitamins / Megavitamin Therapy
High-dose oral or intravenous vitamins, including vitamin C, used in some complementary cancer protocols. This protocol is categorized as Herbs, Supplements, and Natural Substances and is included because people commonly use it as a non-medical, complementary, or supportive cancer-care approach. PROS May have symptom-support, anti-inflammatory, nausea, taste, appetite, relaxation, or laboratory-research rationale depending on the product.
NCI overview explaining that cancer patients may use CAM to cope with treatment side effects, comfort themselves, or try to treat cancer, and that CAM should be discussed with the care team. Used to frame grounding as supportive rather than curative.
Randomized placebo-controlled phase II trial of high-dose IV vitamin C plus docetaxel in metastatic castration-resistant prostate cancer. Did not improve PSA response, toxicity, or clinical outcomes compared with placebo.
VITAMINS randomized clinical trial; combination therapy did not significantly improve time alive and free of vasopressor support compared with hydrocortisone alone.