Although the use of intravenous vitamin C by those with a diagnosis of cancer is considered, by traditional medicine, an ineffective and possibly dangerous therapy, there is accumulating medical research that intravenous vitamin C may improve outcomes. A recent medical study evaluating the effect of adding intravenous vitamin C during chemotherapy for pancreatic cancer demonstrated significant benefits.
Interest in using very high doses of vitamin C as a cancer treatment began as long ago as the 1970s when it was discovered that some properties of the vitamin may make it toxic to cancer cells. Initial studies in humans had promising results, but these studies were later found to be flawed.
Subsequent well-designed, randomized, controlled trials of vitamin C and cancer found no such treatment benefit. Despite the lack of evidence, alternative medicine practitioners continue to recommend high doses of vitamin C for cancer treatment.
Interestingly, the clinical use of intravenous vitamin C has a long history in traditional medicine. It had been used in the treatment of viral infections decades before the discovery of anti-viral medications. It also had been shown to be effective in preventing the life-altering effects of polio. Today it is commonly used in nontraditional medicine in the treatment of cancer.
Laboratory experiments in mice and rats seemed to show that antioxidants may protect cancer cells from chemotherapy medications suggesting that antioxidants are contraindicated with chemotherapy. However, clinical trials have not confirmed these laboratory results.
Many chemotherapies have pro-oxidant properties that are effective against rapidly growing cells like cancer cells. Theoretically using antioxidant compounds may protect cancer cells from the pro-oxidant effects of chemotherapy drugs.
A recent phase I human trial (2018) published in the medical journal Cancer Research evaluated the effect of intravenous vitamin C and usual traditional therapy on advanced pancreatic adenocarcinoma. The study demonstrated that intravenous vitamin C in combination with the usual chemotherapy (gemcitabine) and radiation therapy almost doubled survival time (21.7 months compared to 12.7 months) and the time of no progression of disease increased threefold compared to their control (13.7 months vs 4.6 months).
Indeed, at high doses, vitamin C can act also as a pro-oxidant and as a generator of cancer-killing hydrogen peroxide, potentially enhancing the cancer-killing effects of chemotherapy. One mouse ovarian cancer study in 2014 demonstrated that vitamin C not only enhanced the effectiveness of the chemotherapy drugs carboplatin and paclitaxel, but also reduced chemotherapy-associated toxicity in patients with ovarian cancer.
In addition, the intravenous vitamin C protected normal cells from the toxic effects of radiation therapy. Their conclusions were that intravenous vitamin C aids in the killing of pancreatic cancer cells and protects normal cells from radiation therapy damage ” … making it an optimal agent …” in the treatment of pancreatic cancer.