electrochemical investigation of the interactions of hydroxychloroquine and famotidine in the treatment of patients with covid-19

Drug-drug interactions occur when two or more drugs react with each other. the necessity to pay attention to drug interactions has been felt more in recent years due to the prevalence of coronavirus disease (covid-19). this is an infectious disease caused by the sars-cov-2 virus. most people infected with the virus will experience mild to moderate respiratory illness and recover without requiring special treatment. however, some will become seriously ill and require medical attention. since covid -19 has a viral cause, no specific drug has yet been designed for it, so the lack of coronavirus-specific antiviral drugs has led to several studies reusing previously approved drugs to treat sars-cov-2. chloroquine (cq) and hydroxychloroquine (hcq) are synthetic 4-aminoquinolines. they are used to treat autoimmune diseases. recently, international medical organizations have allowed the treatment of covid -19 in some hospitalized patients with hcq. hcq increases the endosomal ph, which inhibits fusion between sars-cov-2 and the host cell membrane [1]. on the other hand, famotidine is used to treat and prevent ulcers in the stomach, but a recent clinical study showed that when high-dose famotidine was administered to hospitalized covid -19 patients, it reduced intubation and mortality rate [2]. in this study the electrochemical behavior of hcq in the presence of famotidine was investigated using cyclic voltammetry and controlled-potential coulometry techniques in aqueous buffer solution (ph~7). the results indicated that the peak structures and currents have changed and famotidine has reduced the hcq current value in cyclic voltammetry. corresponding products were electrochemically synthesized in aqueous solutions using a carbon electrode in an undivided cell. these products were identified by spectroscopic methods (ft-ir, 1hnmr, 13cnmr and ms) and chromatographic method (hplc). also, the homogeneous rate constants (kobs), based on the suggested electrode mechanism were estimated by comparing the experimental cyclic voltammetric responses with those digital simulated results.