What is dexamethasone and how does it treat COVID-19?

11/11/2020

You might have seen this potent drug mentioned in the news quite a bit lately, especially as a COVID-19 treatment of choice for Donald Trump. In this article, we take a closer look at what exactly this drug is, why is it used and how it works.

Dexa-what?

Dexamethasone is a corticosteroid that goes by a number of different names including:

Decadron
Dexasone
Diodex
Hexadrol
Maxidex
Dexamethasone sodium phosphate
Dexamethasone acetate.

Dexamethasone is sold under a range of brand names

Dexamethasone and COVID-19

Dexamethasone has recently been popularised by Donald Trump as a treatment for COVID-19 and has been used successfully to treat some patients.

The World Health Organisation (WHO) reports that dexamethasone was tested in hospitalised COVID-19 patients during the United Kingdom’s (UK) national RECOVERY clinical trial where it was found to have benefits for critically ill patients.

When administered to patients on ventilators, dexamethasone reduced fatalities by about one third. In patients who required only oxygen to be administered, mortality rates were cut by about one fifth.

In the light of these promising results, the WHO has included by dexamethasone as a treatment option for patients with COVID-19. However, its use has been restricted to patients with severe and critical infections that typically require interventions such as oxygen therapy or ventilation. Administering dexamethasone in the early-stages of COVID-19 infection could be harmful to the patient and, at best, have no benefits at all. Hence, it has not been recommended for use in patients with less severe COVID-19 infections.

How does dexamethasone work for COVID-19 patients?

Infection by the COVID-19 virus prompts the patient’s immune system to fight the virus. Unfortunately, although the immune system is vital in fighting serious diseases such as COVID-19, sometimes the inflammatory response that results is counterproductive and leads to complications such as severe viral pneumonia and ‘cytokine storms’.

Severe viral pneumonia is caused by inflammation of the lungs. Within the lungs, the air sacs (alveoli), where carbon dioxide and oxygen are exchanged, are most vulnerable to inflammation. In response to the inflammation, the body sends fluid chock full of white blood cells into the alveoli. An accumulation of this fluid in the lungs makes breathing difficult and ventilation may be necessary to counter the effects of the excess fluid in the lungs.

Cytokine storms are a slightly different kettle of fish. Coronaviruses (such as COVID-19, SARS and MERS) are notoriously associated with the immune response commonly known as a ‘cytokine storm’. Cytokines are proteins that act as messengers between the immune system and immune cells. A cytokine storm occurs when, in directing the immune cells to attack the region infected by the virus, the body releases more cytokines than required, which causes too much inflammation. The activated immune cells then produce more cytokines, and a dangerous inflammation cycle is evoked, potentially causing severe damage to internal organs and other bodily structures. If left untreated, this will lead to the death of the patient.

Dexamethasone can assist COVID-19 patients suffering from severe inflammation events after their body tries to fight off the virus.

Dexamethasone is used to reduce inflammation. By introducing dexamethasone as a treatment at these severe stages, inflammation can be tempered to an appropriate level. However, if the drug is administered too early, it may weaken the body’s response to the disease, thus harming its ability to effectively fight COVID-19.

What else is dexamethasone used for?

Swelling (oedema), associated with tumours of the spine and brain
Eye inflammation, thyroid and intestinal disorders
Allergic reactions
Certain kinds of autoimmune diseases, like lupus (specifically SLE) and rheumatoid arthritis (RA)
Skin, blood, renal (kidney), asthma and other lung conditions, such as ITP or croup
A variety of cancers, such as leukaemia, lymphoma, and multiple myeloma
Nausea and vomiting associated with some chemotherapy drugs
Loss of appetite in cancer patients who are experiencing severe appetite problems.

As a corticosteroid, it’s helpful in reducing all types of inflammation in the body, including in the inflammation caused by autoimmune conditions and allergies.

Among its numerous applications, dexamethasone is commonly used to treat:

It’s also used to replace steroids in conditions of adrenal insufficiency (basically, where the adrenal glands aren’t producing enough of vital steroids needed by the body to function).

Dexamethasone is effective for a range of conditions including asthma and lung complaints such as croup

Aggression, irritability or agitation
Anxiety, nervousness, changes in mood and depression
Difficulties with thinking, speaking or walking
Vision and eye changes, including blurry or decreased vision, eye pain or tearing up
Decreased urine output
Headaches, fainting and dizziness
An irregular heartbeat or pulse, which may also be fast, slow, or pounding
Noisy, rattling breathing or troubled breathing while at rest, cough or hoarseness
Tingling or numbness of the arms or legs
Pounding in the ears
Swelling of the fingers, hands, feet or lower legs
Increases in weight, hunger and thirst
Abdominal/stomach cramping, burning feeling or pain
Backache
Flushed, dry or darkened skin
Mouth dryness
Extra growth of facial hair in female patients
Fullness or roundness to the face, neck or trunk
Tiredness or weakness
Nausea and vomiting.

What are the side effects of dexamethasone?

As a fairly useful, albeit strong, corticosteroid, dexamethasone may cause a wide variety of side effects including:

Despite this long list, it’s important to note that most patients are only given a short course of dexamethasone, meaning they are likely to experience few, if any, of these side effects. For conditions requiring longer corticosteroid courses, the doctor may recommend moving to prednisone/prednisolone after taking dexamethasone for a period of time.

Got questions?

If you have any questions about COVID-19, dexamethasone or other drugs, or would like advice on safely handling hazardous substances, please contact the Chemwatch team today. Our friendly and experienced staff draws on years of experience to offer the latest industry advice on how to stay safe and comply with Health and Safety regulations.

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