n electrocardiogram. Use of dolasetron injection for the prevention of chemotherapy-induced nausea and vomiting is contraindicated because the risk of QT prolongation is higher with the doses required for this indication; when the injection is used at lower doses (i.e., those approved for post-operative nausea and vomiting) or when the oral formulation is used, the risk of QT prolongation is lower and caution is advised. Tricyclic antidepressants (TCAs) share pharmacologic properties similar to the Class IA antiarrhythmic agents and may prolong the QT interval, particularly in overdose or with higher-dose prescription therapy (elevated serum concentrations).
Phenelzine: Because of the potential risk and severity of serotonin syndrome, use caution when administering dolasetron with other drugs that have serotonergic properties such as Monoamine oxidase inhibitors. If serotonin syndrome is suspected, discontinue dolasetron and concurrent serotonergic agents and initiate appropriate medical treatment. Serotonin syndrome is characterized by rapid development of hyperthermia, hypertension, myoclonus, rigidity, autonomic instability, mental status changes (e.g., delirium or coma), and in rare cases, death.
Phenylephrine; Promethazine: Promethazine carries a possible risk of QT prolongation. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with promethazine include dolasetron.
Pimavanserin: Pimavanserin may cause QT prolongation and should generally be avoided in patients receiving other medications known to prolong the QT interval, such as dolasetron. Dolasetron has been associated with a dose-dependant prolongation in the QT, PR, and QRS intervals on an electrocardiogram. Use of dolasetron injection for the prevention of chemotherapy-induced nausea and vomiting is contraindicated because the risk of QT prolongation is higher with the doses required for this indication; when the injection is used at lower doses (i.e., those approved for post-operative nausea and vomiting) or when the oral formulation is used, the risk of QT prolongation is lower. Coadministration may increase the risk for QT prolongation.
Pimozide: Pimozide is associated with a well-established risk of QT prolongation and torsade de pointes (TdP). Because of the potential for TdP, use of dolasetron with pimozide is contraindicated.
Posaconazole: The concurrent use of posaconazole and dolasetron is contraindicated due to the risk of life threatening arrhythmias such as torsades de pointes (TdP). Posaconazole is a potent inhibitor of CYP3A4, an isoenzyme partially responsible for the metabolism of dolasetron. These drugs used in combination may result in elevated dolasetron plasma concentrations, causing an increased risk for dolasetron-related adverse events, such as QT prolongation. Additionally, posaconazole has been associated with prolongation of the QT interval as well as rare cases of torsade de pointes; avoid use with other drugs that may prolong the QT interval and are metabolized through CYP3A4, such as dolasetron.
Primaquine: Due to the potential for QT interval prolongation with primaquine, caution is advised with other drugs that prolong the QT interval. Drugs with a possible risk for QT prolongation and TdP that should be used cautiously and with close monitoring with primaquine include dolasetron.
Procainamide: Dolasetron should be used cautiously with procainamide. Procainamide is |
