Drug Interactions between Cipro Cystitis Pack and pimavanserin

Consumer information for this interaction is not currently available.

GENERALLY AVOID: Pimavanserin may cause dose-related prolongation of the QT interval. Theoretically, coadministration with other agents that can prolong the QT interval may result in additive effects and increased risk of ventricular arrhythmias including torsade de pointes and sudden death. In a thorough QTc study conducted in 252 healthy subjects, the maximum mean change in QTc interval from baseline was 13.5 msec at twice the therapeutic dosage given to steady state. In 6-week premarketing placebo-controlled effectiveness studies, mean increases in QTc interval were approximately 5 to 8 msec in patients receiving the recommended pimavanserin dosage of 34 mg once daily. Sporadic QTcF values >=500 msec and change from baseline values >=60 msec were observed in subjects treated with pimavanserin, although the incidence was generally similar to that reported for placebo groups. There were no reports of torsade de pointes arrhythmia or differences from placebo in any other adverse reactions associated with delayed ventricular repolarization. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors such as congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia). The extent of drug-induced QT prolongation is dependent on the particular drug(s) involved and dosage(s) of the drug(s).

MONITOR: Coadministration with inhibitors of CYP450 3A4 may increase the plasma concentrations of pimavanserin, which is primarily metabolized by the isoenzyme. According to the product labeling, pimavanserin peak plasma concentration (Cmax) and systemic exposure (AUC) increased by 1.5- and 3-fold, respectively, when given with the potent CYP450 3A4 inhibitor ketoconazole. The interaction has not been studied with other, less potent inhibitors. High plasma levels of pimavanserin may increase the risk of QT interval prolongation, which has been associated with ventricular arrhythmias including torsade de pointes and sudden death.

MANAGEMENT: Coadministration of pimavanserin with other drugs that can prolong the QT interval should generally be avoided. Caution is advised if concomitant use of pimavanserin is required and no alternatives are available, in accordance with the labeling recommendation for use in combination with CYP450 3A4 inhibitors. Patients should be monitored for adverse effects such as peripheral edema and QT prolongation, have regular ECGs to monitor for arrhythmias when the QT interval is prolonged, and the pimavanserin dosage adjusted as necessary. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope.