Packs of dexamethasone anti-inflammatory steroid tablets. Corticosteroids such as this reduce inflammation by inhibiting the production of prostaglandins, chemicals that cause inflammation and aid the sending of pain signals to the brain. Dexamethasone has been shown to reduce mortality in Covid-19 patients that require oxygen or ventilator support. Covid-19 is a respiratory disease caused by the new coronavirus SARS-CoV-2 that can lead to fatal pneumonia.