ISMP issues error alert on new COX 2 inhibitor

Medications with similar names lead to errors

Celebrex, Celexa, or Cerebyx? If the spelling or the pronunciation of these three very different drugs seems confusingly similar, you are not alone.

Concerning Celebrex (celecoxib), a COX 2 inhibitor by Searle/Pfizer that went on the market earlier this year, the Institute for Safe Medication Practices (ISMP) in Warminster, PA, received some 40 documented medication errors within the first two months of its availability through its error reporting system (1-800 23-ERROR). More than a million prescriptions for the drug have been dispensed, according to drug company literature.

Errors found in written, verbal orders

Most of the errors were simple misinterpretations of written orders, but they also included some cases of confusion over verbal orders, according to ISMP. No fatalities were reported and most were caught in time, but on several occasions, patients did receive the wrong drug. In one case, an 80-year-old patient received 20 mg of Celexa twice a day for a month to treat arthritis pain instead of the intended 100 mg of Celebrex twice a day. No serious adverse reactions occurred, but the patient’s condition went untreated for that amount of time.

Celexa (citalopram hydrobromide) is a selective serotonin reuptake inhibitor antidepressant marketed by Forest Pharmaceuticals. Cerebyx, the generic name fosphenytoin, marketed by Parke-Davis, is prescribed for seizures.

"Most errors so far have resulted from written orders, but the potential for verbal errors is also high, especially for practitioners with English as a second language and especially true for spoken accents in which it is difficult to differentiate between l’ and r’ sounds in the middle of words," explains ISMP spokeswoman Rebecca Wilfinger.

Ironically, Celebrex manufacturer Searle originally planned to name the drug Celebra but renamed the drug Celebrex to lessen confusion with the other two. To avoid confusion, ISMP recommends that prescribers include the purpose of the medication when ordering any of the three drugs and that pharmacists seek indications when not included. Prescribers should include the less-similar generic names on the orders, and alerts pertaining to the drugs should be added to computer system alerts.

[For more details, call ISMP at (215) 956-9181.]