What is the role of dexamethasone (corticosteroid) in controlling nausea?

From the Guidelines

Dexamethasone is a highly effective medication for controlling nausea and vomiting, and its use is recommended in specific clinical scenarios, particularly when combined with other antiemetic agents such as 5-HT3 receptor antagonists and NK1 receptor antagonists. For chemotherapy-induced nausea and vomiting, a typical dose is 8-20 mg given intravenously before chemotherapy, followed by oral doses of 4-8 mg twice daily for 2-4 days depending on the emetogenic potential of the chemotherapy regimen 1. The optimal dose and schedule of dexamethasone may vary depending on the specific clinical scenario and the emetogenic potential of the chemotherapy regimen.

Some key points to consider when using dexamethasone for nausea control include:

• Dexamethasone works by inhibiting prostaglandin synthesis and reducing inflammation in the brain's chemoreceptor trigger zone, which helps block the vomiting reflex 1.
• It also has anti-inflammatory effects that reduce tissue swelling that might trigger nausea, particularly in cases of increased intracranial pressure or bowel obstruction 1.
• Side effects to monitor include hyperglycemia, mood changes, insomnia, and increased risk of infection with prolonged use 1.
• Dexamethasone should be used cautiously in patients with diabetes, psychiatric disorders, or active infections, and is typically not recommended for long-term use due to potential adverse effects 1.

In terms of specific clinical scenarios, the following recommendations can be made:

• For chemotherapy-induced nausea and vomiting, a three-drug regimen including single doses of a 5-HT3 receptor antagonist, dexamethasone, and aprepitant given before chemotherapy is recommended for patients receiving highly emetogenic chemotherapy 1.
• For moderately emetogenic chemotherapy, a two-drug combination of palonosetron and dexamethasone is recommended, with the option to add aprepitant if necessary 1.
• For postoperative nausea and vomiting prevention, a single dose of 4-8 mg IV given before surgery is often sufficient 1.
• For palliative care settings, 4-8 mg daily orally or parenterally may be used 1.

Overall, dexamethasone is a valuable medication for controlling nausea and vomiting, and its use should be tailored to the specific clinical scenario and patient needs. The most recent and highest quality study recommends the use of dexamethasone in combination with other antiemetic agents for the prevention of chemotherapy-induced nausea and vomiting 1.

From the Research

Dexamethasone for Nausea Control

• Dexamethasone is a glucocorticoid that has been suggested as a first-line drug for preventing low-level emetogenic chemotherapy- and radiotherapy-induced nausea and vomiting, and in patients with only one or two risks for postoperative nausea and vomiting (PONV) 2.
• The mechanisms of action of dexamethasone for nausea control include anti-inflammatory effects, direct central action, interaction with neurotransmitters, and regulation of the hypothalamic-pituitary-adrenal axis 2.
• Studies have shown that dexamethasone-sparing regimens, which involve using a lower dose or shorter duration of dexamethasone, are not associated with a significant loss in overall antiemetic control in patients undergoing moderately emetogenic chemotherapy (MEC) or anthracycline and cyclophosphamide-containing chemotherapy (AC) 3, 4.
• A meta-analysis of randomized controlled trials found that a short course of dexamethasone (1-2 days) was associated with a lower risk of adverse events compared to a long course (3+ days), with no significant difference in complete response of nausea and vomiting 5.
• A randomized, phase III, noninferiority trial found that dexamethasone-sparing regimens, including metoclopramide or palonosetron, were noninferior to a 3-day dexamethasone regimen in controlling delayed chemotherapy-induced nausea and vomiting after MEC 6.

Efficacy of Dexamethasone for Nausea Control

• Dexamethasone has been shown to be effective in preventing nausea and vomiting in patients undergoing chemotherapy, with a complete response rate of 50-60% 3, 6.
• The efficacy of dexamethasone for nausea control is similar to that of other antiemetic agents, such as metoclopramide and palonosetron 6.
• Dexamethasone-sparing regimens have been shown to be effective in controlling delayed nausea, with a total control rate of 55-60% 4, 6.

Safety of Dexamethasone for Nausea Control

• Dexamethasone is generally well-tolerated, with common adverse events including insomnia, anxiety, and hyperglycemia 2, 5.
• A short course of dexamethasone has been shown to be associated with a lower risk of adverse events compared to a long course 5.
• Dexamethasone-sparing regimens have been shown to be safe and effective, with no significant increase in adverse events compared to a 3-day dexamethasone regimen 6.