• Corpus ID: 545102

Pharmacokinetics of vitamin C: insights into the oral and intravenous administration of ascorbate.

@article{Duconge2008PharmacokineticsOV,
  title={Pharmacokinetics of vitamin C: insights into the oral and intravenous administration of ascorbate.},
  author={Jorge Duconge and Jorge R. Miranda-Massari and Michael J. Gonz{\'a}lez and James A. Jackson and William Warnock and Neil H Riordan},
  journal={Puerto Rico health sciences journal},
  year={2008},
  volume={27 1},
  pages={
          7-19
        }
}
There is a strong advocacy movement for large doses of vitamin C. Some authors argue that the biological half-life for vitamin C at high plasma levels is about 30 minutes, but these reports are the subject of some controversy. NIH researchers established the current RDA based upon tests conducted 12 hours (24 half lives) after consumption. The dynamic flow model refutes the current low-dose recommendations for dietary intakes and links Pauling's mega-dose suggestions with other reported effects… 

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References

SHOWING 1-10 OF 62 REFERENCES
Vitamin C Pharmacokinetics: Implications for Oral and Intravenous Use
TLDR
It is reported here that intravenous doses can produce plasma concentrations 30- to 70-fold higher than the maximum tolerated oral doses, and the role of vitamin C in cancer treatment should be reexamined, and insights from vitamin C pharmacokinetics can guide its clinical use.
Vitamin C Pharmacokinetics after Continuous Infusion in a Patient with Prostate Cancer
TLDR
The information obtained from this preliminary pharmacokinetic assessment of ascorbate at megadoses allows a better understanding of its disposition in cancer patients, and will help to optimize the dosage to be used in a perspective clinical trial in order to maximize the therapeutic benefits.
Vitamin C pharmacokinetics in healthy volunteers: evidence for a recommended dietary allowance.
TLDR
The current RDA of 60 mg daily should be increased to 200 mg daily, which can be obtained from fruits and vegetables, and safe doses of vitamin C are less than 1000mg daily, and vitamin C daily doses above 400 mg have no evident value.
Pharmacokinetic perspectives on megadoses of ascorbic acid.
TLDR
The analysis indicates that both saturable gastrointestinal absorption and nonlinear renal clearance act additively to produce the ceiling effect in plasma concentrations, and there is no pharmacokinetic justification for the use of megadoses of ascorbic acid.
A new recommended dietary allowance of vitamin C for healthy young women
TLDR
Results of a depletion–repletion study with healthy young women hospitalized for 186 +/− 28 days, using vitamin C doses of 30–2,500 mg daily indicate that the Recommended Dietary Allowance for young women should be increased to 90 mg daily.
Effects of high dose ascorbate administration on L-10 tumor growth in guinea pigs.
TLDR
Ascorbate concentrations sufficient to kill tumor cells can be safely achieved in solid tumors in vivo, suggesting a possible role for high dose intravenous ascorbates in treating cancer.
Vitamin C, titrating to bowel tolerance, anascorbemia, and acute induced scurvy.
Cytotoxicity of ascorbate, lipoic acid, and other antioxidants in hollow fibre in vitro tumours
TLDR
The effect of ascorbate on doxorubicin efficacy was concentration dependent; low doses were protective while high doses increased cell killing, suggesting tumoricidal concentrations may be achievable in vivo.
Pharmacologic ascorbic acid concentrations selectively kill cancer cells: action as a pro-drug to deliver hydrogen peroxide to tissues.
  • Qi Chen, M. Espey, M. Levine
  • Biology, Medicine
    Proceedings of the National Academy of Sciences of the United States of America
  • 2005
TLDR
Human pharmacokinetics data indicate that ascorbate at concentrations achieved only by i.v. administration may be a pro-drug for formation of H(2)O(2), and that blood can be a delivery system of the pro- drug to tissues.
...
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