The Proton Pump Inhibitors Use and COVID-19 from Prior to Vaccination Perspective: A Review

The coronavirus infectious disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) has been a huge challenge, affecting directly or indirectly the human race worldwide. Many COVID-19-related risk factors have been identified. Various drugs, including proton pump inhibitors (PPIs), have been claimed to increase the risk of acquiring or affecting the outcome of COVID-19 prior to the availability of vaccines. The aim of this review was to summarize the uncertain role of PPI use on the SARS-CoV-2 infection and COVID-19 clinical course, including both some well-established and presumptive indications to these potent inhibitors of gastric acid secretion, before vaccinations against COVID-19 were implemented on a massive scale.

Although iatrogenic hypochlorhydria alters human microbiota and impairs the nonspecific innate immunity, increasing the likelihood of gastrointestinal and pulmonary infections, published data on the relationship between SARS-CoV-2 positivity and clinical manifestations of COVID-19 are quite inconclusive. On the contrary, the beneficial role of PPI use in the prevention of the upper gastrointestinal bleeding, particularly in at-risk patients receiving dual antiplatelet treatment and/or concomitant anticoagulation, constituting a significant proportion of COVID-19 patients, has been well-documented. Furthermore, PPIs have been marked as a potential antiviral remedy, just like many already existing repurposed drugs, that merit further studies in search of successful anti-CO-VID-19 pharmacotherapy.

The controversial role of PPIs on the SARS-CoV-2 infection and COVID-19 severity propounded in the past should not prevent the use of these potent inhibitors of gastric acid secretion in well-established clinical indications.