These are water-soluble molecules and, for their chemical nature, can pass the cell membranes; however, the presence of the hydroxyl group in the HCQ makes it more polar and less lipophilic [8]. Moreover, the accumulation of CQ and HCQ in intracellular compartments is due principally to the side chain and both have enantiomers (R and S isomers). Researches also demonstrated that the R-HCQ is present in the blood at higher concentrations than S-HCQ. These results suggested the stereoselective processes in the metabolism of the molecule [9].