Sound-alike meds: Simple misunderstandings may have serious consequences

Error Alert

A student pharmacist recently reported a mix-up between the seasonal allergy drug cetirizine (Zyrtec—McNeil) and the antidepressant sertraline (Zoloft—Pfizer). A nurse left a telephone prescription on the pharmacy’s voicemail system for 10 mg of cetirizine. However, because of the nurse’s pronunciation, the pharmacist misheard the order as sertraline and dispensed 100 mg of sertraline to the patient. The patient caught the error when she discovered an antidepressant Medication Guide inside the bag with the prescription bottle. 

Just as they do with handwritten prescriptions, prescribers and their agents should indicate the purpose of the drug when calling in any prescriptions, particularly when left on a voicemail system. Medication names, especially those with a history of being confused, should always be spelled out. Additionally, digits used to indicate dosage should be sounded out (e.g., one–five instead of 15). As always, providing patient education, especially for new prescriptions, is a good strategy for intercepting errors.

What’s in a name? 

The similar-sounding medications Kapidex (dexlansoprazole—Takeda Pharmaceuticals) and Casodex (bicalutamide—AstraZeneca) have led to reported instances of both written and verbal prescriptions being dispensed in error. Kapidex is indicated for healing of erosive esophagitis, maintenance of healed erosive esophagitis, and treatment of symptomatic, nonerosive gastroesophageal reflux disease. It is available as 30-mg and 60-mg delayed-release capsules for oral administration. Casodex is indicated for use in combination therapy with a luteinizing hormone-releasing hormone analog for the treatment of stage D2 metastatic prostate cancer. Casodex is available as 50-mg tablets for oral administration. 

Patients who receive either drug in error could be unnecessarily subjected to unintended effects and/or adverse events. Specifically, Casodex is contraindicated in women. To reduce the potential for medication errors, please take time to verify written or verbal orders and build an alert into your computer system. Consider adding this pair of medications to your commonly confused drug name list. 

The Institute for Safe Medication Practices (ISMP) received a report from a pharmacist who had a prescription for Kapidex called in from a doctor’s office. However, the office nurse misspelled the drug as “Capadex,” probably because she heard the drug name pronounced by the doctor and then transcribed it phonetically. When the pharmacist tried to enter the medication as spelled into the pharmacy computer, he could not find it. The pharmacist then queried his coworkers about whether the intended prescription might be for Casodex. Meanwhile, one of the other pharmacists did a Google search on “Capadex” to see if it was an actual product. He found many listings for Capadex as well as a listing for Kapidex. 

Capadex is a combination of acetaminophen and propoxyphene—similar to darvocet—that is not available in the United States. It is available in Australia and New Zealand, however, as well as online, and at least one website advertises that no original prescription is needed for Capadex. FDA has been notified about this new issue associated with the brand name Kapidex. Given that the name is being confused with both Casodex and the foreign product Capadex, this might be an instance where a name change is appropriate.

In a similar case, a doctor’s office sent an electronic prescription to the patient’s pharmacy but selected the wrong drug name. The physician intended to prescribe Vesicare (solifenacin succinate—Astellas Pharma) for overactive bladder but inadvertently clicked on Vesanoid (tretinoin—Roche Laboratories), which is used to induce remission of acute promyelocytic leukemia. 

The pharmacy technician entered the prescription for generic tretinoin; however, the pharmacy was unable to dispense the medication because the patient’s pharmacy benefit manager required prior authorization. The technician faxed a request to the provider, and the doctor’s office replied that it was Vesicare that was actually intended for the patient. Both of these products are available in 10-mg solid oral dosage forms, increasing the risk of confusion. Using strategies such as tall man lettering can help differentiate these products on computer screens. 

Product safety testing: You can help

Pharmacists, pharmacy technicians, and other health care practitioners interested in furthering medication safety and error prevention can make a difference. Med-ERRS, a subsidiary of ISMP, is looking for assistance to help evaluate medication labels, drug packaging, and proposed drug names prior to submission by pharmaceutical and biotech companies for FDA approval. The process is fun and easy, and a small honorarium is offered. For more information or to sign up, visit and click on “Become a Reviewer.”