Antiemetic Therapy and QT Interval Prolongation

Antiemetic Options

Lorazepam is the safest antiemetic option for patients at risk of QT prolongation as it does not cause QT interval prolongation and is considered safe from a cardiac arrhythmia perspective 1
The American College of Cardiology recommends considering alternative antiemetics, such as lorazepam, for patients at high risk of QT prolongation 1
Palonosetron is the only 5-HT3 antagonist without a QT prolongation warning in its label, making it a preferred option when a 5-HT3 antagonist is necessary 2

Female gender increases susceptibility to drug-induced QT prolongation 1
Electrolyte abnormalities, especially hypokalemia and hypomagnesemia, enhance the risk of QT prolongation 1, 3
The American College of Cardiology recommends correcting electrolyte abnormalities, particularly hypokalemia and hypomagnesemia, before administering potentially QT-prolonging antiemetics 3
The Journal of the National Comprehensive Cancer Network recommends considering dexamethasone as an alternative antiemetic for patients with low emetogenic risk conditions, due to its lower risk of QT prolongation compared to 5-HT3 antagonists 4

For patients at high risk of QT prolongation requiring antiemetic therapy, lorazepam should be the first choice 1
Before administering any potentially QT-prolonging antiemetic, obtain baseline ECG and correct electrolyte abnormalities 3
Stop treatment with QT-prolonging antiemetics if the QTc is > 500 ms on monitoring 3