e caution when administering dolasetron with other drugs that have serotonergic properties such as lithium. 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.
Lomefloxacin: Quinolones have been associated with QT prolongation and in rare cases, torsades de pointes. Ciprofloxacin should be used with caution in patients receiving drugs that prolong the QT interval, such as dolasetron.
Long-acting beta-agonists: Dolasetron has been associated with a dose-dependant prolongation in the QT, PR, and QRS intervals on an electrocardiogram (ECG). 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. Drugs with a possible risk for QT prolongation and torsade de pointes (TdP) that should be used cautiously and with close monitoring with dolasetron include the beta-agonists. Beta-agonists may be associated with adverse cardiovascular effects including QT interval prolongation, usually at higher doses and/or when associated with hypokalemia.
Loop diuretics: The manufacturer warns that the coadministration of dolasetron with diuretics associated with hypokalemia could increase the risk of QT prolongation. Patients taking certain diuretics may develop an electrolyte abnormality that may lead to cardiac dysrhythmias and/or QT prolongation. Hypokalemia or hypomagnesemia may occur with administration of potassium-depleting drugs such as loop diuretics increasing the potential for cardiac arrhythmias. Potassium levels should be within the normal range prior to and during therapy with dolasetron.
Loperamide: Use loperamide and dolasetron together with caution. At high doses, loperamide has been associated with serious cardiac toxicities, including syncope, ventricular tachycardia, QT prolongation, torsade de pointes (TdP), and cardiac arrest. Dolasetron has also been associated with a dose-dependent prolongation in the QT, PR, and QRS intervals. 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, such as for post-operative nausea and vomiting, or when the oral formulation is used, the risk of QT prolongation is lower and caution is advised.
Loperamide; Simethicone: Use loperamide and dolasetron together with caution. At high doses, loperamide has been associated with serious cardiac toxicities, including syncope, ventricular tachycardia, QT prolongation, torsade de pointes (TdP), and cardiac arrest. Dolasetron has also been associated with a dose-dependent prolongation in the QT, PR, and QRS intervals. 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 injecti |
