Dexamethasone Use in Neuro-Oncology: Balancing Efficacy and Toxicity

Introduction Corticosteroids are widely used in neuro-oncology, with dexamethasone the preferred option for symptom control. However, optimal dosing remains unclear. This review evaluated high- versus low-dose dexamethasone regimens in adults with brain and spinal tumours. Methods A systematic review was conducted in accordance with PRISMA-P guidelines. Ovid (MEDLINE, Embase, Emcare), PubMed, and the Cochrane Library were searched from inception to July 2025. Eligible studies compared low- with higher-dose regimens in adults with brain or spinal tumours. Outcomes included neurological improvement, adverse effects, and survival. Results From 742 citations, four studies (n = 249) were included: three randomised controlled trials and one retrospective cohort. In brain metastases, low-dose dexamethasone (4–8 mg/day) was as effective as 16 mg/day for short-term functional improvement, while higher doses increased toxicity. The retrospective cohort showed most patients improved within 24–48 hours on modest cumulative doses (~ 17 mg), with no added benefit from higher or prolonged treatment. In metastatic spinal cord compression (MSCC), high- and low-dose dexamethasone regimens achieved comparable neurological and pain outcomes, though higher doses were associated with more adverse events. Conclusions Current evidence suggests low-dose dexamethasone regimens are as effective as high-dose regimens for most patients, while higher doses increase toxicity. As neurological improvement typically occurs within 24–48 hours, prolonged high-dose therapy may offer limited additional value. Further multicentre studies are required to establish optimal dosing, duration, and tapering.