FDA and Janssen Issue Warnings about Cisapride
Serious cardiac arrhythmias have developed in more than 270 patients taking cisapride, 70 of whom died, Janssen and FDA stated. Review of these spontaneously reported cases showed that about 85% of the patients had at least one risk factor for development of a cardiac arrhythmia. Factors included use of another drug that prolongs the QT interval on the ECG, inhibits the metabolism of cisapride by cytochrome P-450 3A4 isoenzyme, or depletes serum electrolytes. Also noted as a risk factor was the presence of a disorder that could predispose a patient to a cardiac arrhythmia.
Janssen issued a "Dear Doctor" letter alerting prescribers to changes in the labeling for Propulsid, particularly the boxed warning and sections on drug interactions and dosage and administration.
In brief, cisapride therapy should not be started if the patient's ECG shows a QTc interval of more than 450 milliseconds, the patient has an electrolyte disorder, or the patient takes any of the following types of drugs:
- Macrolide antibiotic, such as clarithromycin, erythromycin, or troleandomycin;
- Antifungal agent, such as fluconazole, itraconazole, or ketoconazole;
- Protease inhibitor, such as indinavir or ritonavir;
- Phenothiazine, such as prochlorperazine or promethazine;
- Class IA or III antiarrhythmic agent, such as quinidine, procainamide, or sotalol; and
- Tricyclic antidepressant, such as amitriptyline.
Cisapride also should not be prescribed if the patient takes nefazodone, maprotiline, sertindole, bepridil, or sparfloxacin or drinks grapefruit juice. Diuretic therapy is not a contraindication to cisapride therapy, but the patient's serum electrolytes must be monitored.
The new Propulsid "medication guide," written for patients, also reflects these changes.
FDA announced that it plans to hold a public advisory committee hearing on Apr. 12 to discuss the safety of cisapride therapy. Janssen had issued a previous warning about cardiac risks from cisapride therapy in June 1998.
[ASHP posted an update about cisapride in April, 2000.]