What medication can be given to a patient with nausea and prolonged QT (quantitative T) interval?

From the Guidelines

For a patient with nausea and a prolonged QT interval, ondansetron and other 5-HT3 receptor antagonists should be avoided due to the risk of further QT prolongation, and instead, consider using domperidone 10 mg 3 times a day as it has fewer central side effects and a lower risk of QT prolongation compared to other anti-emetics 1. When managing nausea in patients with prolonged QT intervals, it is crucial to select medications that minimize the risk of further QT prolongation.

• Domperidone, a dopamine D2-receptor antagonist, is a viable option as it does not readily cross the blood-brain barrier, resulting in fewer central side effects than metoclopramide 1.
• The recommended starting dose of domperidone is 10 mg 3 times a day, and although escalation to 20 mg 4 times a day has been reported, this should be avoided for cardiovascular safety considerations 1.
• Other options like phenothiazine antipsychotics (e.g., prochlorperazine, chlorpromazine) can reduce nausea and vomiting by inhibiting dopamine receptors in the brain but have not been studied in gastroparesis or compared prospectively with other anti-emetics 1.
• Neurokinin (NK-1) receptor antagonists (e.g., aprepitant, tradipitant, casopitant, rolapitant) may also improve nausea and vomiting but are not the first line of treatment due to their cost and availability 1. It is essential to monitor the patient's QTc interval regularly when administering these medications, especially with repeated dosing, to minimize the risk of cardiac complications 1.

From the FDA Drug Label

5 WARNINGS AND PRECAUTIONS

1. 2 QT Prolongation Electrocardiogram (ECG) changes including QT interval prolongation have been seen in patients receiving ondansetron. In addition, postmarketing cases of Torsade de Pointes have been reported in patients using ondansetron tablets. Avoid ondansetron tablets in patients with congenital long QT syndrome.

The FDA drug label does not answer the question.

From the Research

Medication Options for Nausea with Prolonged QT Interval

• Ondansetron is a commonly used medication for treating nausea and vomiting, but it has been shown to prolong the QT interval and increase the risk of ventricular dysrhythmias 2, 3, 4, 5.
• The studies suggest that ondansetron can cause QT prolongation, particularly in patients older than 18 years of age 4.
• A dose of 1 mg of ondansetron may be effective in preventing postoperative nausea and vomiting with minimal or no QTc interval prolongation 5.
• Other medications, such as antiarrhythmic drugs, macrolide and fluoroquinolone antibiotics, and typical and atypical antipsychotics, can also prolong the QTc interval and require close monitoring in intensive care unit (ICU) patients 6.
• It is essential to consider the potential risk of QT prolongation when administering medications, especially in patients with pre-existing QT interval prolongation or other risk factors for Torsade de Pointes 6.

Considerations for Medication Administration

• The administration of ondansetron should be carefully considered in patients with prolonged QT intervals, and alternative medications may be necessary 2, 3, 4, 5.
• Close monitoring of the QTc interval and electrocardiogram (ECG) checks are crucial when administering medications that can prolong the QTc interval, especially in ICU patients 6.
• The dosage of ondansetron should be carefully selected, as higher doses (8 mg) may be associated with higher rates of QTc prolongation, while lower doses (4 mg) may be safer 2, 3.