Rx Update: September 2000
Mary Ross, R.Ph., M.B.A.
Peer Review Status: Internally Reviewed
The manufacturer of divalproex (Depakote®), valproate sodium (Depacon®), and valproic acid (Depakene®) has updated the labeling for these agents. A black box warning discussing their association with life-threatening pancreatitis has been added. Patients and guardians are warned that abdominal pain, nausea, vomiting, and/or anorexia can be symptoms of pancreatitis and require prompt medical evaluation.
Oral Poliovirus Vaccine, Live (OPV)
Routine production of OPV has been discontinued in the U.S. Since January 1, 2000, the Centers for Disease Control and Prevention (CDC) Advisory Committee on Immunization Practices (ACIP) has recommended exclusive use of the injectable inactivated poliovirus vaccine (IPV). The use of an IPV-only schedule for routine childhood polio vaccination in the U.S. eliminates the risk for vaccine-associated paralytic poliomyelitis associated with OPV.
Troglitazone
There had previously been a number of changes in the indications for use and recommendations for monitoring liver function in patients receiving troglitazone (Rezulin®). However, in March 2000 after further review of safety data on troglitazone, the manufacturer of the drug agreed to the FDA's request to remove the drug from the market. The FDA took this action based on a review that indicates that other agents in the thiazolidinedione class of antidiabetic agents - rosiglitazone (Avandia®) and pioglitazone (Actos®) - offer the same benefits without as great a risk of severe liver toxicity.
Alosetron
Alosetron (Lotronex®), a serotonin 5-HT3 antagonist, indicated for the treatment of women with diarrhea-predominant irritable bowel syndrome, has had recent labeling changes to reflect new safety information. These changes were prompted by post-marketing reports of serious complications of constipation including obstruction, perforation, impaction, toxic megacolon, and secondary ischemia which, in some cases, required surgery. New information regarding contraindications and recommendations for the discontinuation of therapy because of constipation have been added to the package insert and the patient information summary.
Thioridazine
Thioridazine (Mellaril®) is an antipsychotic agent used in the treatment of schizophrenia, dementia, organic brain syndrome, and depression. Prompted by the FDA, the manufacturer has added a "black-boxed" warning because the agent has been shown to prolong the QT interval and has been associated with torsades de pointes-type arrhythmias and sudden death. Information about drugs that are contraindicated with thioridazine has also been added to the package insert, as well as, recommendations for baseline ECG studies performed on patients prior to initiation of therapy.
Cisapride
Cisapride (Propulsid®) is a prokinetic drug that normalizes and restores motility throughout the gastrointestinal tract; it was FDA-labeled for the treatment of gastroesophageal reflux disease. The manufacturer is no longer marketing the drug after receiving reports of serious cardiac arrhythmias including ventricular tachycardia, ventricular fibrillation, torsades de pointes, and QT prolongation. Cisapride is now only available under an investigational limited-access program to appropriate patients for whom other therapies are not effective and meet clearly defined eligibility criteria.