Paracelsus Paradox and Drug Repurposing for Cancer


  • Tomas Koltai Former Director of the Centro Gallego Hospital of Buenos Aires, Buenos Aires, Argentina



Dose is one of the parameters that any pharmacologist seriously considers when studying the effects of a drug. If the necessary dose to achieve a desired pharmacological effect is in a toxic or very toxic range for human use, the drug will probably fall out from further research. The concentration that a drug can reach at its target organ or cell is a direct consequence of the administered dose and its pharmacodynamic properties. Basic researchers investigate at the cellular level or eventually with xenografts. They use different concentrations of the drug in order to determine its cellular effects. However, in many cases, these concentrations require doses that are in the toxic range or well beyond any clinically achievable level. Therefore, in these cases, research is in the realm of Toxicology rather than therapeutics. This paper will show some examples about this exercise in futility which is time and resource consuming but that pullulates the pages of many prestigious journals. Many seasoned researchers seem to have forgotten the Paracelsus Paradox.


Dose bias, Drug repurposing, Cancer, Metformin, Statins


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How to Cite

Koltai, T. (2021). Paracelsus Paradox and Drug Repurposing for Cancer. Journal of Oncology Research, 3(2), 46–54.


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