Prescription mix-ups do happen, can be serious

Michael R. Cohen, president of the Institute for Safe Medication Practices, wrote this for the "Check-Up Blog" on Philly.com.

Giving a prescription to the wrong pharmacy patient is a common error.

A study conducted by the Institute for Safe Medication Practices, found this error happens about once in every 1,000 prescriptions. With close to four billion prescriptions dispensed from pharmacies each year, an average of seven errors happen each month at every pharmacy across the United States.

Giving a correctly dispensed prescription to the wrong patient can happen for several reasons:

First, a mistake can be made when placing the prescription in a bag for pickup. These errors often stem from working on more than one patient's prescription at a time, and then placing the medicine in the wrong bag. Most people pick up their medicine and leave the pharmacy without ever opening the bag. Furthermore, many pharmacies do not require their workers to open the bag before ringing up the sale.

People may notice the error once they get home, especially if the medicine looks different than expected. But a government study shows only about half of patients confirm their name on the prescription label, and only about three-quarters confirm the medicine's name before taking it. As a result, many people have taken the wrong medicine.

A second problem is that sometimes pharmacy workers select the wrong bag of medicines for customers. Employees who believe they know their customers by sight may not always ask customers to state their full name and date of birth. Or caregivers, friends, and even family members who pick up prescriptions for the patient may not know the patient's date of birth. So the wrong customer's bag may be chosen if there are medicines in the pickup area for customers with the same or similar last names. Using an address to identify customers is not ideal, as people with the same last name often live together.

Taking the wrong medication can have serious consequences. For example, a pregnant woman who intended to fill a prescription for an antibiotic to treat an infection was accidentally given another woman's prescription for methotrexate instead. Both women had the same last name and similar first names. The pregnant woman took one tablet of methotrexate before noticing the error. Methotrexate is a medicine used to treat certain cancers and other conditions, such as rheumatoid arthritis and psoriasis. The medicine prevents cell growth and should never be taken by a pregnant woman. It can cause birth defects in the brain, bone, and heart, or cause a miscarriage. The pregnant woman was seen in the emergency department, but it was too early to determine whether the unborn child had been harmed.

Additionally, taking the wrong medication means you aren't getting what your doctor prescribed for you. For example, a patient who had been prescribed an antibiotic for a serious bacterial infection accidentally received another patient's depression medicine, sertraline (Zoloft). After 10 days, the patient became very ill as the infection raged on untreated. Another patient had been prescribed a pain reliever but instead received another patient's prescription for allopurinol, a gout medicine. After days of pain without relief, she noticed the error and called the pharmacy.

Sometimes customers accidentally given the wrong medicine have realized the error and taken the drugs anyway. In one case, a woman who had picked up her prescription for Premarin (estrogen) found another patient's medicine also in the bag when she arrived home. The medicine was amitriptyline (Elavil), a medicine to treat depression. Later, a pharmacist received a call from a local hospital to tell her the woman was in the emergency department after taking 30 amitriptyline tablets in what appeared to be a suicide attempt.

Another consequence of pharmacy errors is that confidential information is shared inappropriately. The full name and address of the patient, along with the drug name, are on the pharmacy label. For sensitive medicines, such as psychiatric medicines or medicines that treat human immunodeficiency virus (HIV), patients may be deeply troubled that another person is aware of this information.

So, yes, these errors do happen, and they are not uncommon, as nearly every community pharmacist would admit.