Dexamethasone is a synthetic steroid – a medicine that reduces inflammation by mimicking anti-inflammatory hormones produced by the body.

How does it work?

Dexamethasone is a synthetic (man-made) corticosteroid. Corticosteroids are naturally-occurring chemicals produced by the adrenal glands located above the kidneys. Corticosteroids affect the function of many cells within the body and suppress the immune system. Corticosteroids also block inflammation and are used in a wide variety of inflammatory diseases affecting many organs.

This drug works by dampening down the body’s immune system.

Coronavirus infection triggers inflammation as the body tries to fight it off.But sometimes the immune system goes into overdrive and it’s this reaction that can prove fatal – the very reaction designed to attack infection ends up attacking the body’s own cells.

Dexamethasone calms this effect.

It’s only suitable for people who are already in hospital and receiving oxygen or mechanical ventilation – the most unwell.

The drug does not work on people with milder symptoms, because suppressing their immune system at this point would not be helpful.

 

What was the trial?

The results come from the Recovery (Randomised Evaluation of Covid-19 therapy) trial, conducted by the University of Oxford.

According to the scientists who carried out the trials, one in three deaths could be prevented among patients on ventilators.

For patients on oxygen, it could prevent one death in five.

There was no significant benefit for patients who were not receiving respiratory support.

 Uses of Dexamethasone:

Dexamethasone is used to treat conditions such as arthritis, blood/hormone/immune system disorders, allergic reactions, certain skin and eye conditions, breathing problems, certain bowel disorders, and certain cancers. It is also used as a test for an adrenal gland disorder (Cushing’s syndrome).