d with a dose-dependant prolongation in the QT, PR, and QRS intervals on an electrocardiogram. Dolasetron injection is contraindicated for use for the prevention of chemotherapy-induced nausea and vomiting because the risk of QT prolongation is higher with the doses used 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. Local anesthetics have a possible risk for QT prolongation and TdP based on varying levels of documentation and should be used with caution with dolasetron.
Chloroquine: Due to a possible risk for QT prolongation and torsade de pointes (TdP), dolasetron and chloroquine should be used together cautiously. 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 and caution is advised. Chloroquine administration is associated with an increased risk of QT prolongation and torsades de pointes (TdP). The need to coadminister chloroquine with drugs known to prolong the QT interval should be done with a careful assessment of risks versus benefits and should be avoided when possible. In addition, chloroquine inhibits CYP2D6. The coadministration of chloroquine with drugs that prolong the QT interval and are CYP2D6 substrates may result in increased plasma concentrations and an increased risk of QT prolongation. Drugs that may prolong the QT interval and also are CYP2D6 substrates include dolasetron.
Chlorpromazine: Due to a possible risk for QT prolongation and torsade de pointes (TdP), dolasetron and chlorpromazine should be used together cautiously. 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 and caution is advised. Phenothiazines have been associated with a risk of QT prolongation and/or torsade de pointes (TdP). This risk is generally higher at elevated drugs concentrations of phenothiazines. Chlorpromazine is specifically associated with an established risk of QT prolongation and TdP; case reports have included patients receiving therapeutic doses of chlorpromazine. Agents that prolong the QT interval could lead to torsade de pointes when combined with a phenothiazine, and therefore are generally not recommended for combined use.
Cimetidine: Coadministration of dolasetron and cimetidine, a nonselective inhibitor of cytochrome P450, increased the blood concentrations of dolasetron's active metabolite by 24%.
Ciprofloxacin: Due to an increased risk for QT prolongation and torsade de pointes (TdP), caution is advised when administering dolasetron with ciprofloxacin. Ciproflox |
