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Introduction to Medication Errors

Discover what medication errors are and the recommended pharmaceutical best practices to avoid them.
Hi, everyone. My name is Shao-Chin Chiang, currently the deputy director of pharmacy in Koo Foundation Sun Yet-Sen Cancer Center Taipei, Taiwan. Today, we are going to discuss a very important issue in pharmacy practice, which is prevention and management of medication safety. Medication safety has been a priority of health-system pharmacy practice in recent years. This movement and this practice emphasis probably driven by the landmark publications.
There are several publications. The most important one probably is the IOM report, publishing in 2000.
The title of the report is:
To Error is Human: building a safer health system. The title says that to error is human doesn’t mean that to error is a mass or is forgivable. Instead, because to error is human, so we need to as much as possible to prevent any error that could be done by human being. So, the report highlighted the pervasive nature of injuries associate with both appropriate and inappropriate use of medications. And it reframing medical errors as a chronic threat to public health, which means the error has been existed in the medical practice for a long time. And it really causes a lot of problems, and the most of years, could cause death.
And a medication error is one of the major components of medical errors. Ok, then before we going to discuss about the pervasive and management of medication safety, we have to deal with the terminology. Because there are so many terminologies describing the errors that really confuse us, If we could differentiate the difference between them, then we will have a clear concept in discussing this issue. The first one is drug-related problems. This term refers to the events associated with the drug therapies that can or do hamper optimal patient health outcomes.
It includes medication errors, adverse drug reactions, adverse drug events, and side effects. Ok, so far, you have seen these four terms, Following, we are going to discuss what’s the difference between the four terms, and we need to emphasis they are so important. So, when we talk about these different terms, you have clear concept. And also, we commonly see another term called medication misadventures, which means iatrogenic hazards or incidents associated with indicated drug therapy resulting in patient harm that can be attributable to error, immunologic response, or idiosyncratic response. So, the term, medication misadventures, looks very similar to drug-related problems.
It could be done because of errors, or it could be done because of patient’s idiosyncratic response, patient’s own attribute to respond to the medication differently. All could be called medication misadventures. So, these two terms are pretty much interchangeable. Medication errors refer to the errors or mistakes in the medication use process. The medication use process refers to prescribing, transcribing, dispensing, administration and monitoring. So, these errors and mistakes occur during this process that may result in negative outcomes. Medication errors,
we could categories them by impact on patients, that means hours of year, the damage, the harm to the patients. And there are 9 categories, from category A without error to category I, error occurs and most severe result is death. Secondly, we could category them by where they exist within the medication use process. So, we could category them as prescribing errors, transcribing and/or interpretation errors, dispensing errors, administration errors, or monitoring errors. Adverse drug reactions, abbreviate as ADRs, is one of the drug-related problems, but they are unexpected, unintended responses to a drug that require some types of medical response, for example, we need to discontinue the drugs or decrease the dose of drugs or change the frequency of drugs.
Otherwise, it will result in negative outcome.
So, be careful ADRs refer to unexpected, and we need to do something about it. It may or may not be the result of a medication error. It could be allergic reactions, which is a patients’ special response to medications, or idiosyncratic reactions. In contrast, a side effect is also one type of drug-related problem, but they are expected well known reactions, but they don’t require patient management. We could still let the patient keep taking the medication without changing anything. Adverse drug events, we abbreviate it as ADEs. These are the ADRs,
remember they are unexpected, unintended. These ADRs those result in injury. But, some of the expected, well-known reactions to medications that are severe enough to require extensive medication management are included in this category. Drug-related morbidity is the failure of a drug to achieve its intended health outcome due to unresolved drug-related problems.
We also heart sentinel events a lot. So, it means unexpected incidents resulting in death or the potential for serious physical or psychological injury.
The sentinel, the word, actually means that it requires immediate investigation and response. Medication errors that do not lead to negative health outcomes, that we could divide in two categories. The first one is latent injuries, which means a propensity or predisposition for harm during the medication use processes. The second type is potential injuries. These are the mistakes in medication-use process that have the potential to cause an injury but did not, either by luck or because they were intercepted.
Also, there are two terms that we will see in the lecture. Errors of commission that means the errors can occur when the patient receives either a correct drug or an incorrect drug. Errors of omission refer to errors is that a patient fail to receive drugs that can be beneficial. So, errors of commission mean the drug has be taken by the patient already, and errors of omission, the drug did not go into patient’s mouth or go into patient’s body. That’s the healthcare professionals’ errors because of omit in therapeutic agent.

Happening this week: Chiang will first explore medication errors, different aspects of safety in this activity before moving onto ethics in a later activity.

Chiang first gives a background to how the world views medication safety issues, before moving on to explain some essential terminology.

Medication Error Key Points

An IOM report, published in 2000 is titled: To Error is Human: building a safer health system. It discusses the inevitability of human errors and the possible efforts to prevent them. It also highlighted the pervasive nature of injuries associated with medication use, concluding that medical errors are chronic threat to public health.


  • Drug-related problems, drug therapy-associated events that hamper optimal patient health outcomes. Includes medication errors, adverse drug reactions, adverse drug events, and side effects.
  • Medication misadventures, iatrogenic hazards, or incidents that can be attributable to error, immunologic response, or idiosyncratic response. Similar to drug-related problems, the terms are quite interchangeable.
  • Medication errors, errors, or mistakes in the medication use process (prescribing, transcribing, dispensing, administration, or monitoring). Can be categorised based on the severity of impact or by medication process. Medication errors with no negative health outcomes are further classified into latent and potential injuries.
  • Adverse drug reactions (ADR), unexpected and unintended responses to a drug that require a medical response. It may or may not be the result of a medication error.
  • Side effects, expected or well-known reactions. Don’t require patient management.
  • Adverse drug events, ADRs that result in injury or severe side effects that require extensive medication management.
  • Drug-related morbidity, event where drugs fail to achieve the intended health outcome due to unresolved drug-related problems.
  • Sentinel events, unexpected incidents resulting in death, or the potential for serious physical or psychological injury.
  • Errors of commission, errors occurred when the patient receives a drug.
  • Errors of omission, error occurred when the drug did not enter the patient’s system.

To learn more about medication errors, check out this course: “Good Pharmacy Practice: Pharmaceutical Services from Taipei Medical University.

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Good Pharmacy Practice: Pharmaceutical Services

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