Vitamin C

BCCT plans to write a summary on vitamin C. While our summary is in development, you can visit these sites:

Click the image to open the brochure.

Before using this therapy, consult your oncology team about interactions with other treatments and therapies. Also make sure this therapy is safe for use with any other medical conditions you may have.


A review found intravenous vitamin C use generally safe, except in patients with renal impairment or glucose 6 phosphate dehydrogenase deficiency.1 Although at least one case study reported a kidney stone occurrence during IV vitamin C treatment,2 prospective studies found no association between a high daily intake of vitamin C and the risk of stone formation, even when consumed in large doses, in both men and women3

The About Herbs and CAM-Cancer summaries of vitamin C and the The Centre for Health Innovation's monograph list several contraindications, adverse reactions, herb-drug interactions and herb-lab interactions. For instance, in some studies, vitamin C was found to reduce the effectiveness of some chemotherapy drugs. Serious harm can occur using high-dose vitamin C in people with glucose-6-phosphate dehydrogenase (G6PD) deficiency, an inborn metabolism error. Read the summaries for more information:

Highlighted Video

Integrative oncologist and BCCT advisor Brian Bouch, MD, briefly discusses antioxidants and high-dose vitamin C (IV).

TRC Natural Medicines Database provides an even more extensive listing and discussion of adverse reactions, contraindications, and herb-drug interactions: TRC Natural Medicines: Vitamin C (subscription required)

Neil McKinney, ND, lists a number of cautions and contraindications not listed in other sources, such as avoiding megadoses of vitamin C in leukemia, as it can paradoxically increase malignant cell proliferation. He also cautions not to use during the same week as Artemisinin therapy, nor in tumors with high risk of tumor lysis syndrome and hemorrhage.4

Patients on regular dialysis treatment may be at increased risk for oxalate supersaturation in IV vitamin C use.5

BCCT strongly advises that you speak with your oncology physician if you are thinking about or are taking high-dose vitamin C. BCCT also strongly advises that if you use high dose vitamin C, you seek care from a healthcare professional knowledgeable and experienced in administering this treatment to people with cancer.


BCCT does not recommend therapies or doses, but only provides information for patients and providers to consider as part of a complete treatment plan. Patients should discuss therapies with their physicians, as contraindications, interactions and side effects must be evaluated.

Dosage recommendations are available from these sources:

Integrative Programs, Protocols and Medical Systems

For more information about programs and protocols, see our Integrative Programs and Protocols page.

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