High-Dose Intravenous Vitamin C in Cancer Care

A Supportive Therapy Offered by Vitamin Clinics

High-dose intravenous vitamin C (IVC), sometimes referred to as pharmacologic ascorbate, is increasingly used internationally as a supportive therapy alongside chemotherapy and immunotherapy. At Vitamin Clinics, we offer high-dose IV vitamin C as an adjunctive treatment, designed to support patients during conventional cancer care — not as a replacement, but as part of a coordinated, medically supervised approach.

Unlike oral vitamin C supplements, intravenous administration allows vitamin C to reach plasma concentrations that have been studied in oncology settings and shown to have distinct biological effects.

Why intravenous vitamin C is different

When taken orally, vitamin C absorption is tightly regulated by the digestive system, limiting the levels that can circulate in the bloodstream. Intravenous delivery bypasses these limits, allowing clinicians to achieve significantly higher plasma concentrations that are not achievable with oral supplementation.

At these pharmacologic levels, vitamin C has been shown in clinical and translational research to:

• Influence oxidative stress within the tumour micro-environment

• Affect cancer cell metabolism and redox balance

• Interact with the way certain cancer treatments impact tumour cells

These properties form the scientific basis for using high-dose IV vitamin C alongside standard cancer treatments.

Evidence-supported benefits as an adjunct to cancer treatment

Improved quality of life during treatment

One of the most consistently reported benefits of high-dose IV vitamin C is its impact on quality of life during cancer treatment.

Clinical studies and reviews have associated IV vitamin C with improvements in:

• Cancer-related fatigue

• General wellbeing and energy levels

• Nausea and gastrointestinal discomfort

• Appetite and sleep quality

For many patients, these improvements help make intensive treatment periods more manageable, supporting day-to-day functioning while undergoing chemotherapy or immunotherapy.

Support for chemotherapy tolerability

Several studies examining high-dose IV vitamin C alongside chemotherapy have reported reduced treatment-associated toxicity, without evidence that vitamin C interferes with the anti-cancer effects of chemotherapy.

In research involving ovarian and pancreatic cancers, pharmacologic ascorbate has been associated with:

• Lower severity of common chemotherapy side effects

• Improved patient-reported outcomes

• Better overall treatment tolerance

This suggests a role for IV vitamin C in supporting patients through demanding treatment regimens, helping them remain on therapy where clinically appropriate.

Promising clinical results in pancreatic cancer

A particularly encouraging development comes from a randomised controlled clinical trial in metastatic pancreatic cancer. Patients receiving standard chemotherapy (gemcitabine and nab-paclitaxel) in combination with high-dose intravenous vitamin C demonstrated:

• Improved overall survival

• Longer progression-free survival

• No increase in treatment-related toxicity

• No negative impact on quality of life

While ongoing research will further define where this therapy fits best, this study represents one of the strongest human clinical signals to date supporting high-dose IV vitamin C as a meaningful adjunct in oncology care.

Growing interest alongside immunotherapy

Vitamin C plays a recognised role in immune system regulation. Preclinical research has shown that pharmacologic doses of vitamin C may favourably influence the tumour micro-environment and immune activity.

As a result, there is increasing interest in using high-dose IV vitamin C alongside immunotherapies, including immune checkpoint inhibitors. While clinical evidence in this area is still developing, early findings support its potential as a supportive immune-modulating therapy.

Safety, screening, and medical oversight

High-dose intravenous vitamin C has demonstrated a favourable safety profile in clinical studies when delivered under appropriate medical supervision.

At Vitamin Clinics, patient safety is central to our approach. Before treatment, patients are assessed to ensure IV vitamin C is suitable, with screening typically including:

• Review of medical history

• Assessment of kidney function where appropriate

• Coordination with existing oncology care

We strongly encourage patients undergoing cancer treatment to discuss IV vitamin C with their oncologist or specialist team, ensuring all care is aligned and appropriately timed.

A supportive, integrative approach at Vitamin Clinics

At Vitamin Clinics, high-dose intravenous vitamin C is offered as part of a supportive, patient-centred model of care. Our focus is on helping patients:

• Better tolerate chemotherapy or immunotherapy

• Maintain quality of life during treatment

• Access adjunctive therapies within a medically governed framework

Every patient is treated as an individual, and therapy plans are designed to complement — not replace — conventional cancer care.

Considering high-dose IV vitamin C?

If you are currently undergoing cancer treatment and are interested in exploring whether high-dose intravenous vitamin C may be appropriate for you, we recommend:

• Speaking with your oncologist or specialist clinician

• Contacting Vitamin Clinics for an initial consultation

• Ensuring treatment is integrated safely within your existing care plan

Our clinical team is always happy to discuss suitability, screening, and what to expect from treatment.

To learn more about high-dose IV vitamin C and our supportive cancer-care services, please contact Vitamin Clinics or book a consultation through our website.

Contact us to find out more

References

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2. Monti DA, Mitchell E, Bazzan AJ, et al.Phase I evaluation of intravenous ascorbic acid in combination with gemcitabine and erlotinib in patients with metastatic pancreatic cancer.PLoS ONE. 2012;7(1):e29794.doi:10.1371/journal.pone.0029794

3. Bodeker KL, Allen BG, Smith MC, et al.Pharmacologic ascorbate improves survival in patients with metastatic pancreatic cancer treated with gemcitabine and nab-paclitaxel: A randomized clinical trial.Redox Biology. 2023;62:102665.doi:10.1016/j.redox.2023.102665

4. Ma Y, Chapman J, Levine M, Polireddy K, Drisko J, Chen Q.High-dose parenteral ascorbate enhanced chemosensitivity of ovarian cancer and reduced toxicity of chemotherapy.Science Translational Medicine. 2014;6(222):222ra18.doi:10.1126/scitranslmed.3007154

5. Allen BG, Bodeker KL, Smith MC, et al.First-in-human phase I clinical trial of pharmacologic ascorbate combined with radiation and temozolomide for newly diagnosed glioblastoma.Clinical Cancer Research. 2019;25(22):6590–6597.doi:10.1158/1078-0432.CCR-19-0120

6. Carr AC, Vissers MCM, Cook JS.The effect of intravenous vitamin C on cancer- and chemotherapy-related fatigue and quality of life.Frontiers in Oncology. 2014;4:283.doi:10.3389/fonc.2014.00283

7. Klimant E, Wright H, Rubin D, Seely D, Markman M.Intravenous vitamin C in supportive cancer care: A review of safety, efficacy, and patient outcomes.Current Oncology. 2018;25(2):e135–e144.doi:10.3747/co.25.3790

8. National Cancer Institute (NCI).Intravenous Vitamin C (PDQ®) – Health Professional Version.Updated regularly.https://www.cancer.gov/about-cancer/treatment/cam/hp/vitamin-c-pdq

9. Mikirova N, Casciari J, Riordan N, Hunninghake R.Clinical experience with intravenous vitamin C in oncology patients.Journal of Translational Medicine. 2013;11:191.doi:10.1186/1479-5876-11-191