Three drugs, three similar names, some close calls

Watch out for dispensing mix-ups if you are taking any of the following medications: Ranexa, Prenexa and Pradaxa.  These drugs are all prescribed for different reasons although their names can look and/or sound very much alike. We’ve had some close calls reported to us lately through our National Medication Error Reporting Program, so the risk of a mix-up bears mentioning since getting the wrong pill could lead to serious harm. 

One pharmacist reported that when he received a prescription for Pradaxa, he initially thought it was Ranexa. Pradaxa is used for a heart rhythm disturbance called atrial fibrillation, where the heart’s upper chambers don’t beat normally. This increases the risk that blood clots will form. If these reach the brain they can cause a stroke, and may also cause serious injury elsewhere. Ranexa is used for a different kind of heart problem - angina or chest pain that occurs when the blood vessels in your heart are obstructed and can’t carry enough oxygen.

Someone getting Ranexa in error would be in danger of stroke as a result of inadequate treatment of their heart rhythm disturbance.

On the other hand, since Pradaxa affects the blood’s ability to clot, someone who gets Pradaxa when they’re supposed to be taking Ranexa for angina might be in danger of hemorrhage. The drug is also ineffective in treating angina.  

Fortunately, the pharmacist in the case above took the time to speak with the patient and learned that the prescription was a replacement for Coumadin, which also affects clotting and is used for atrial fibrillation.

Ranexa has also been confused with Prenexa, a prenatal vitamin. In one case a pregnant woman took Ranexa in error for a year, after her pharmacist misread this prescription. The patient went on to obtain a refill each month, thinking it was her vitamin. The error was eventually discovered a year later when it became time for a prescription renewal and the patient called the pharmacy to ask them to obtain a new prescription for prenatal vitamins. When the pharmacist checked her drug profile she noticed that prenatal vitamins weren’t listed in the computer for that patient. Fortunately, there was no known harm to the patient from erroneously taking Ranexa.

Unlike the previous case, the pregnant patient who received Ranexa in error refused to speak with the pharmacist when the original prescription was dispensed and the pharmacist tried to initiate a discussion. That’s a big mistake. The pharmacist didn’t know she was pregnant and needed a prenatal vitamin. If she did, the error probably wouldn’t have happened. Keep this case in mind because it points out that speaking with your pharmacist provides a valuable opportunity to discover a dispensing error. In fact this is one of the primary recommendations we have to prevent mix-ups. Always make sure the pharmacist knows the reason you are taking a medicine.

Most medicines with look-alike names are not used to treat the same condition, so having your doctor list the reason for the medicine right on the prescription you give the pharmacist helps to ensure the correct medicine is provided. Also, be sure to take time to read the drug information leaflet that comes with your medicine. If it isn’t what you expect, it could indicate that something’s wrong.

Fortunately, most doctors are already using electronic prescriptions that produce legible drug names that are significantly less likely to be misread. Electronic prescribing is an important way to prevent errors, so I believe it should also be an important consideration when selecting a physician. It isn’t perfect though, so don’t let your guard down. I’ve seen multiple cases where doctors and nurse practitioners accidentally choose the wrong name from a computer listing when two different drugs with similar names are listed right above one another on the computer screen.

Finally, inspect the medicine before you leave the pharmacy to be sure it looks as expected if you are refilling a prescription. Use Google images if the prescription is new or visit the drug information section on our website. Pill images are provided there, along with up-to-date drug information. 

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