Abstract

Mucus is an integral part of the respiratory physiology. It protects the respiratory tract by acting as a physical barrier against inhaled particles and microbes. Excessive inflammation in conditions such as COVID-19 can result in overproduction of mucus which obstructs the airway. Build-up of mucus can also contribute to recurrent airway infection, causing further obstruction. This article summarizes the current understanding and knowledge of respiratory mucus production and proposes the role of cytokine storm in inducing sudden mucus hypersecretion in COVID-19. Based on these cascades, the active constituents that inhibit or activate several potential targets are outlined for further research. These may be explored for the discovery and design of drugs to combat cytokine storm and its ensuing complications. Nasal blockage or respiratory congestion is among the most common symptoms experienced in primary care as well as tertiary care. It can be particularly severe and even lethal in COVID-19 due to the formation of mucus plugs. Transmission of COVID-19 appears to occur primarily through dispersal of droplets generated from the respiratory tract when an infected person talks, coughs, or sneezes. Large amounts of the SARS-CoV-2 virus have been reported in sputum and nasal specimens, which account for the transmission through respiratory droplets.