Dexamethasone, an anti-inflammatory drug that has been known since the 1960s, this week became the first to be approved by medical authorities to treat severe cases of covid-19.

Dexamethasone was tested in the UK as part of a large study of existing drugs that can be used to treat the new coronavirus.

It proved useful in decrease the chances of death in patients of hospitalized covid-19. The UK medical services made it available to hospitals immediately.

These are several key questions of this new advance in the fight against the coronavirus.

1. What is it?

Dexamethasone is a steroid, a medicine that reduces inflammation by acting like the anti-inflammatory hormones naturally produced by the body.

2. How does it work?

This drug works by buffering the body’s immune system.

When it comes to covid-19, both the virus itself and the body’s reaction to it, cause inflammation.

Graphic
BBC

But sometimes the immune system quickens. That reaction can be fatal– The same body response designed to attack infection ends up attacking the patient’s own cells.

Dexamethasone calms this effect.

That is why this drug only suitable for people who are already in the hospital and who receive oxygen or mechanical respiration, that is, the most serious.

The medicine does not work in people with milder symptoms and suppressing your immune system at that point is not helpful in fighting disease.

Click here to see the BBC interactive

Click here to see the BBC interactive

3. How effective is it?

According to the scientists who conducted the trials, one in three deaths could be prevented among patients who are connected to respirators.

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

DemethasoneDemethasone
THE PRESS / BBC

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

4. How was it tested?

The results come from the clinical trial called Recovery, made by the Oxford University, in the United Kingdom.

Researchers are testing whether medications that already exist in the world to treat other conditions may also be helpful in treating covid-19.

About 2,100 patients received a 6 mg daily dose of dexamethasone in the tests. Their progress was compared to a random sample of just over 4,300 patients who received no further treatment.

A dose of dexamethasoneA dose of dexamethasone
Dexamethasone is a steroid drug. THE PRESS / .

Scientists hope dexamethasone can eventually be used as part of a set of medications that, when combined, can further reduce deaths.

So far it is recommended for adults, not including pregnant or lactating women.

5. How available is the drug?

Dexamethasone is a low-cost drug that already exists worldwide in considerable quantities.

In the UK, treatment costs the equivalent of $ 6.80 per day per patient.

A box of dexamethasoneA box of dexamethasone
Dexamethasone is a medicine widely available in the world. THE PRESS / .

It was first manufactured in 1957 and was available for use in Europe in the early 1960s. Because it has been around for so long, the drug is no longer under patent.

That means many companies can do it and it is widely available worldwide.

This is particularly good news for developing countries, and the results of these tests have been welcomed by the World Health Organization.

6. What was it used for?

The medicine can help treat various diseases involving inflammation in the body or conditions in which the immune system is overloaded.

Severe asthma, for example, can cause inflammation of the airways and lungs, as well as severe allergic reactions or to treat painful and inflamed joints.

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Dexamethasone has been used since the 1960s. THE PRESS / Science Photo Library

Dexamethasone is also useful in autoimmune conditions like rheumatoid arthritis or lupus, which are caused by the immune system mistakenly attacking the body.

7. What are its side effects?

The common side effects Dexamethasone used for other conditions include anxiety, trouble sleeping, weight gain, and fluid retention.

The rarer side effects They include eye disorders, blurred vision, and bleeding.

However, patients with coronavirus only need a relatively low dose, which limits the side effects.