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Intravenous vitamin C in the supportive care of cancer patients

Vitamin C deficiency might occur more often in patients with cancer for the four following reasons

  • Lack of oral intake
  • decreased bioavailability
  •  tissue utilization
  • oxidative stress

IVC can safely administered  to treat Vitamin C deficiency based on symptoms and could improve inflammation, fatigue, and quality of Life .

How Vitamin C is administered in cancer patients as supportive care during the post-adjuvant or the incurable advanced setting?

It recommended the clearance of IV C before chemotherapy administration. Giving 5–25 g IV C over a period of 30–120 minutes is safe for cancer adults  to decrease inflammation, allow for optimal repletion of the body’s antioxidant stores, and possibly support qol. In addition, 500–4000 mg oral vitamin C daily is safe during the intervals between IV C treatments.

Doses of IV C greater than 15 g given over a period of 30 or fewer minutes have been found in vitro and in vivo to have a pro-oxidative effect when blood concentrations exceed 3–4 mm/L

The effects of adding IVC to chemotherapy are unknown with respect to overall efficacy and that vitamin C could potentially decrease treatment efficacy despite any positive effect on symptoms

If the decision is made to provide IV C in with chemotherapy It is  recommended to be administered  before chemotherapy, followed by a 30- to 60-minute break, or that it be given 12–72 hours after chemotherapy with attention to the half-life and clearance of the chemotherapy.

In the supportive care setting, IV C given 1–3 times per week for 1–4 months in combination with oral vitamin C could improve or prevent deficiency, promote wound healing, lessen inflammation, improve quality of life , function status, and potentially lessen the side effects of systemic treatment.

Rational approach for using intravenous (IV) and oral vitamin C in the supportive care of cancer patients


  • Presumptive vitamin C deficiency or depletion, together with fatigue, anemia of chronic disease, reduced oral intake, history of surgery or radiation to the gastrointestinal tract, history of malabsorption, treatment with chemotherapy having intestinal or mucosal side effects, slow wound healing, or infection
  • Symptoms of fatigue, muscle weakness, arthralgia, myalgia, neuropathy, bleeding gums, poor wound healing, lower extremity edema, poor oral intake, loss of appetite, pain, or depression
  • Cancer patients in supportive care and, with cautious consideration, patients receiving adjuvant treatment who might be experiencing symptoms that limit continuation of treatment or that interfere significantly with quality of life


  •  Deficiency of G6PD (normal: 4.6–13.5 U/g hemoglobin)
  • Uncontrolled serum glucose above 300 mg/dL (16.7 mmol/L)


  • Renal insufficiency: use of IV C is at the discretion of the provider if creatinine exceeds 2.0 mg/dL.
  • Hypercalcemia or oxaluria: use of IV C is at the discretion of the provider.
  • Metal storage diseases: In the presence of hemochromatosis or Wilson disease, regular monitoring is recommended. Exacerbation of those conditions might necessitate discontinuation of IV C.
  •  Iron overload because of a history of frequent transfusion.
  • Caution should be used during adjuvant therapy with curative intent because of limited data about treatment efficacy.

Possible side effects

  • Finger-stick glucose monitoring could be abnormal for 1–6 hours after IV C.
  • Side effects reported in clinical trials providing high-dose IV C have included nausea, dizziness, dry mouth, fatigue, perspiration, and weakness. Such effects are not likely to occur with 5–25 g (low-dose) IV C; however, caution is advised.

Frequency and duration

  • During chemotherapy and for 1–4 months after, IV C could be given 1–3 times weekly.
  • Suggested dosing for oral vitamin C: 250–2000 mg twice daily, ongoing at the discretion of the provider


E. Klimant,MD  H. Wright,ND D. Rubin,ND et al.Intravenous vitamin C in the supportive care of cancer patients: a review and rational approach. Curr Oncol  . 2018 Apr;25(2):139-148. doi: 10.3747/co.25.3790. Epub 2018 Apr 30.

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