The full scope of action for intravenous vitamin C (IVC) is yet to be discovered. As we continue to learn more novel mechanisms of intravenous vitamin C, the clinical potential of this therapy continues to evolve.
It is common practice in the integrative oncology setting to use high dose intravenous vitamin C, infused over 1-3 hours several days a week. In high doses, vitamin C exerts an anti-cancer effect by increasing hydrogen peroxide in the tumor environment, creating a pro-oxidant environment.
Although single doses of vitamin C can reach high levels in the blood, it is quickly eliminated with a half-life time of about two hours. A recent study looked at the effects of continuous administration of intravenous vitamin C via slow drip infusion over twenty hours.
The study consisted of 24 patients, who mostly had metastatic disease and undergone several rounds of chemotherapy and radiation. During chemotherapy white blood cell counts typically drop, which is disadvantageous for survival. The study’s aim was to monitor if continuous intravenous vitamin C (over 20 hours) could have an effect on white blood cell counts; specifically looking at neutrophils and lymphocytes.
Pre-treatment measures indicated most patients in this study had vitamin C deficiency. During IVC treatment, this deficiency was corrected as ascorbate (vitamin C) levels increased to reach a plateau. Following treatment, most patients demonstrated improved lymphocyte count with the largest effect being in patients with the lowest initial lymphocyte count. Interestingly enough, for lymphocytes the most substantial improvement occurred at the lowest doses of IVC (150 and 300 mg/kg/day).
Neutrophil to lymphocyte ratio (NLR) is another endpoint to consider, as it is a useful prognostic factor. Lower values of NLR indicate improved survival. The study demonstrated IVC may reduce NLR levels thus improving prognosis for cancer patients.
IVC is a well tolerated treatment that is safe and comes with few adverse effects. Most common side effects include nausea, dry skin and fatigue. There appears to be a dose-dependent effect with most side effects occurring as the dose of IVC is escalated.
While continuous 20-hour vitamin C infusion is impractical, a shorter infusion time (1-3h) of vitamin C followed by repeated oral vitamin C replenishment (i.e. 500-1000mg every 1-2 hours) may produce a similar outcome.