Dexamethasone – the potential downside

Dexamethasone – the potential downside

Brain tumours often cause swelling in the brain and this swelling makes the pressure effect of the brain tumour worse. Symptoms therefore can be exacerbated – headaches may be worse, or patients can be drowsy or the neurological deficits such as arm and leg weakness are exaggerated. For many years, corticosteroids (typically dexamethasone) have been used to reduce the swelling around brain tumours. Starting dexamethasone can be very effective in controlling symptoms caused by brain tumours such as glioblastoma (GBM), other malignant gliomas, metastatic brain tumours, low grade gliomas (astrocytomas, oligodendrogliomas) and benign tumours like meningiomas. Often this improvement occurs within hours. So dexamethasone is a very useful drug for short term control of symptoms.


This is a CT scan showing a left frontal metastatic tumour (bright area) with significant surrounding oedema/swelling (dark areas). This is when dexamethasone can be very helpful in reducing the symptoms from the swelling. Once the tumor is removed however, the need for dexamethasone often quickly reduces.

We are all very familiar with the side effects of dexamethasone when its use is prolonged. It commonly causes weight gain, high blood sugar (making diabetes worse), muscle weakness, mood and behavioural changes, sleep disturbance, suppression of the immune system etc – the list goes on. So the use of dexamethasone should be limited to try to reduce or avoid some of these unpleasant side effects.

But there may be other reasons to avoid or limit the use of dexamethasone – because dexamethasone may adversely affect survival in people with malignant glioma (GBM, glioblastoma). A study published earlier this year (Pitter et al, Brain, 139: 1458-71) provided evidence that the use of dexamethasone during radiotherapy was associated with shorter survival in patients with GBM. These authors also used a mouse model to show that dexamethasone decreased the survival benefit of radiotherapy.

So what does this mean? It is generally accepted that the long term use of dexamethasone should be avoided if at all possible to avoid the unpleasant and sometime nasty effects of chronic use. The recent evidence though also strongly suggests that the use of dexamethasone should be minimised in the early stages of treatment. The following may be useful guidelines:

  • The routine practice of maintaining patients on dexamethasone during radiotherapy in case they develop swelling is probably not justified and could be potentially harmful. Its use should be stopped if patients are asymptomatic and given only if a patient was to develop symptomatic oedema
  • Steroids like dexamethasone are not needed in patients with asymptomatic brain tumours, including gliomas, GBM, and metastases
  • Long term use should be minimised whenever possible

There is also an obvious need to have other medications that can help control the symptoms of cerebral swelling associated with brain tumours. Such agents are currently not available.


By Prof David Walker, Neurosurgeon

Prof David Walker is a neurosurgeon and spinal surgeon at BrizBrain & Spine. He has a special clinical interest in brain tumours and is actively involved in conducting research to help find a cure for this disease. Prof Walker is  also the Managing Director of the Newro Foundation, a research organisation that conducts research into brain and spine conditions.


Patient and staff safety is our highest priority at Briz Brain & Spine.

For patients with appointments, if you are suffering any symptoms such as fever, dry cough, sore throat, tiredness or shortness of breath or have recently travelled interstate, overseas or been in contact with someone who has returned from interstate or overseas, or have been in contact with a confirmed case of COVID-19, please contact our friendly reception team before attending the clinic. A telehealth appointment may be an alternative method of speaking with our surgeons.

Protecting the health of our staff is vital to ensure they can continue to provide great service.  Patients are encouraged to prepay accounts over the phone prior to appointments or via payWave or other contactless payment methods. Patients are also asked to complete the Patient Details Form and sign the Privacy Policy Agreement electronically prior to their appointment. These forms can be found under our Contacts page on the website or by clicking here. Please note, patients are asked to bring only ONE support person to their appointment and maintain appropriate social distances to help reduce the risk of Covid-19 transmission.

During this current outbreak of Covid-19 coronavirus we want to assure all of our patients that we will continue to implement procedures to maintain a hygienic clinical environment. This includes:

-          Disinfecting and wiping down all treatment surfaces

-          Regular cleaning of rooms and shared equipment

-          Thorough cleaning of all communal items including reception chairs, tables, door handles, pens and other shared items

-          All staff have access to infection control procedures and training to implement these as necessary

We are carefully monitoring the directions and advice of Queensland Health, the Australian Government Department of Health and the World Health Organization. In the meantime, it is still business as usual and our doors are open.

Briz Brain & Spine wishes to apologise for the inconvenience caused and thanks you for your cooperation and understanding during this unprecedented situation.