The role of N-acetyl cysteine and some other clinical antidotes in the treatment of patients with COVID-19; review of the current evidence

Anti-viral and anti-cytokine drugs have been proven to be inadequate in ceasing the progression of the novel coronavirus disease, and severe cases are often associated with death or severe chronic injuries. In this respect, N-acetyl cysteine (NAC) has anti-oxidant, anti-inflammatory, and immune-modulating effects and has been revealed to be beneficial in the treatment and prevention of this virus. High-dose oral NAC (1200 mg) can improve adaptive immunity by increasing lymphocyte glutathione levels and regulating neutrophil function during the COVID-19 development. Given that the majority of these patients suffer from hypoxemic respiratory failure and require oxygen supplementation in hospitals, hyperbaric oxygen therapy (HBOT) appears to be an alternative treatment. In fact, HBOT can increase the circulation and delivery of oxygen under high pressures, making the tissue uptake more efficient and improving hypoxia in patients with COVID-19. In addition, low-doses of naltrexone can interact with angiotensin-converting enzyme 2 (ACE2), disrupt the binding of ACE2 to the receptor-binding domain, and have anti-inflammatory and suppressive properties of pro-inflammatory cytokines. Therefore, due to the ability of the low-dose of this drug in preventing the progression of this disease, it can be recommended as an adjunct drug with an immunomodulatory role in combination with other anti-viral drugs in patients with COVID-19. Finally, there appears to be a significant association between vitamin K and thiamine deficiency with the severity of COVID-19. These vitamins play an important role in the coagulation system and suppress inflammation. Therefore, they can be used as a supplement or treatment to improve the outcomes of COVID-19.