High-Dose Intravenous Vitamin C in Cancer Care: Why Responses Vary and How Precision Matters
High-dose intravenous vitamin C (HDIVC), also known as pharmacological ascorbate, has re-emerged in oncology research as a promising adjunctive supportive therapy. While it is not a standalone cure for cancer, clinical studies indicate that when administered at appropriate pharmacological doses, it can provide meaningful benefits for some patients—including improved survival in specific contexts, better quality of life (QoL), and reduced chemotherapy-related side effects. However, not every patient experiences the same level of improvement. This variability is not necessarily evidence that HDIVC “does not work,” but often reflects differences in how the therapy is implemented: dosage, frequency, integration with other treatments, practitioner expertise, and individual patient factors. The same method can yield very different outcomes depending on these variables.