Ascorbic acid (vitamin C, ascorbate) is a key water soluble antioxidant that, when administered in
doses well above its recommended dietary allowance, may have preventative and therapeutic value against a
number of pathologies. The intravenous administration of high dose ascorbate (IVC) has increased in popularity
among complementary and alternative medicine practitioners: thousands of patients received IVC, at an average
dose of 0.5 g/kg, without significant side effects. While IVC may have a variety of possible applications, it has
generated the most interest for its potential use in treating cancer.
Medical records of patients with cancer treated with IVC at the Riordan Clinic were retrospectively
reviewed. Cancer patients, for whom plasma ascorbate concentration data before and after treatment were
available, along with C-reactive protein (CRP) measurements, were chosen for analysis.
The results of the analysis can be summarized as follows. IVC produces peak plasma ascorbate
concentrations on the order of ten millimolars with lower peak plasma concentrations obtained in cancer patients
as compared to healthy subjects. Cancer patients who are deficient in vitamin C prior to therapy tend to achieve
lower plasma levels post infusion. High inflammation or tumor burdens, as measured by CRP or tumor antigen
levels, tend to lower peak plasma ascorbate levels after IVC. When compared to patients with localized tumors,
patients with metastatic tumors tend to achieve lower post infusion plasma ascorbate concentrations.
The data indicate that, while potentially therapeutic plasma ascorbate concentrations can be
achieved with IVC, levels attained will vary based on tumor burden and degree of inflammation (among other
factors). Evidence suggests that IVC may be able to modulate inflammation, which in turn might improve outcomes
for cancer patients. IVC may serve as a safe, adjunctive therapy in clinical cancer care.