Topic Resources
Medication errors are mistakes made by health care professionals and patients when medications are prescribed, given, taken, or stored. Medication errors can make people ill and allow diseases to worsen. Worldwide, the cost of medication errors is estimated to be more than $40 billion annually. (See also Overview of Medication Safety and Effectiveness.)
Medication errors may be caused by the following:
People become confused and take medications incorrectly.
Doctors choose the wrong medication or write a prescription for the wrong dose.
Caregivers incorrectly read the label of the drug container and give the wrong medication or dose.
Caregivers give a medication to the wrong person.
The pharmacist or person incorrectly stores the medication, weakening the medication’s strength.
People use an expired medication.
People take a medication with food when the medication is best absorbed on an empty stomach, or without food when food is needed to prevent side effects.
Medication errors most commonly result from people’s confusion about when and how to take medications, causing them to take the wrong medication or dose. Common reasons for confusion include people putting more than one kind of medication in a single bottle, worn-off instructions on the medication bottle, not understanding the instructions on a medication bottle, having more than one bottle of the same medication, and having so many bottles of medications that people become unsure which one to take when (and which ones have already been taken).
Using medication organizers
Photo courtesy of Robert S. Porter, MD.
Medication organizers can be helpful, particularly when people take several different medications a day. These organizers have separate compartments for each day of the week and up to 4 different times of day. People or their caregivers place a week's worth of medications in the appropriate compartment. For example, if a medication is prescribed to be taken once a day in the morning, they would place one dose in the "morning" compartment of each day. At the appropriate time of day, people take all the medications in that particular compartment. Because all medications in a compartment are taken at the same time, it does not matter that different medications are mixed together. In addition to being a reminder for people, these organizers let caregivers see whether people have taken their medications. Some pharmacies can pre-package medications to help with adherence.
Understanding prescriptions
People should be sure they understand how and when to take a medication when they pick up a prescription. If they do not understand, they should ask their pharmacist to explain how to take their medications.
Prescribing medications
Doctors sometimes make errors when prescribing medications, especially among certain groups of people. Older adults, pregnant people, and children are particularly at risk because they typically require different medications, different doses, or both. Other errors involve drug interactions, in which one drug increases or decreases the effect of another drug.
Drug interactions are more likely to occur in people who take many medications. To minimize this risk, doctors need to know all medications their patients are taking—including those prescribed by other health care professionals and over-the-counter medications and dietary supplements (including medicinal herbs). People should keep a written list of all their current medications and dosages and bring the list to every health care appointment or emergency department visit. If there is any doubt as to which medications are being used, people are instructed to bring all their medications to their health care appointments for review.
Dispensing and administering medications
Medications may be given incorrectly in institutions. A medication may be given to the wrong person, at the wrong time, or by the wrong route. Certain medications must be given slowly when given by vein, and some medications cannot be given at the same time. Many institutions now have computerized pharmacy systems that dispense each dose of the person's medications labeled with a bar code that is scanned and matched with the person's identification bracelet. Such systems may help decrease the incidence of medication errors.
Storing medications properly
Medications must be stored in the proper manner. For example, many medications must be kept away from heat, and some medications must be refrigerated. Mail-order pharmacies must be careful that medications do not get too hot during shipping. If people store medications incorrectly at home, medications are likely to decrease in strength long before the stated expiration date. For example, many people store their medications in the bathroom medicine cabinet, but this is not an ideal storage place because of the heat and humidity. A recommended temperature range for medications is described in the prescribing information.
People should check the label to see whether a medication needs to be stored in the refrigerator or kept cool. On the other hand, unnecessary precautions may make it harder for people to take medications as directed. For example, unopened insulin should be refrigerated, but an open bottle in active use often can be stored safely outside the refrigerator. Additionally, if children do not have access to the medication, medications can be stored with a non–childproof lid.
Taking expired medications
Expired medications are often ineffective because the medications deteriorate with time. Some medications (such as aspirin or tetracycline) deteriorate into toxic substances and can actually be harmful if used past the expiration date. Thus, medications should not be used beyond their expiration date.Expired medications are often ineffective because the medications deteriorate with time. Some medications (such as aspirin or tetracycline) deteriorate into toxic substances and can actually be harmful if used past the expiration date. Thus, medications should not be used beyond their expiration date.
