6: Unintended Medication Outcomes
- Define an unintended drug outcome.
- Name factors that contribute to medication errors.
- Explain why a patient's medication non-adherence may not be intentional.
6.0: Overview of Unintended Medication Outcomes
When considering the occurrence or prevention of unintended outcomes of medication use, error taxonomy and classification can help to guide follow-up actions and prioritize efforts for improvement, when applicable. The classification system for untoward medication-related events is not mutually exclusive. Events may be classified into more than one event category.
6.1. Medication Errors
Medication errors refer to preventable events that lead to inappropriate medication use or harm to a patient. Medication errors can occur at any stage of the medication use process, including prescribing, verifying/preparing, dispensing, administering, or monitoring. Examples of medication errors at each step of the medication use process are described in the table below. One important note about medication errors is that the majority of errors do not result in harm to the patient.
Medication Use Process Step |
Example of Medication Error |
|---|---|
|
Prescribing |
Prescribing a medication at a dose that is inappropriate for their weight, height, gender, or end-organ (renal/liver) function. |
|
Verifying/Preparing |
Reconstituting a medication in the incorrect volume of fluid, results in an unintended concentration. |
|
Dispensing |
Giving or dispensing a medication to the incorrect person. |
|
Administering |
Administering a medication via the incorrect route. |
|
Monitoring |
Failure to perform required monitoring for a high-alert medication. |
6.2 Near Misses
A near-miss medication error is a subclassification that refers to the inappropriate use of a medication that did not reach the patient. Such events, often also described as “good catches”, can significantly contribute to the understanding of important process gaps that could lead to patient harm if not identified/remedied before the medication reaches the patient.
6.3 Adverse Drug Events
Adverse Drug Events (ADEs) are injuries that result from the use of the medication. ADE’s may or may not be related to medication errors. When ADEs are not related to a medication error, they are considered non-preventable. The terms “Non-preventable ADE” and “Adverse Drug Reaction (ADR)” refer to such occurrences.
Preventable Adverse Drug Events involve injury/harm that results from inappropriate medication use. They are medication errors that result in injury or harm. This is a particularly important classification of unintended medication outcomes for medical-legal reasons, and because the circumstances that lead to the event have proven, by definition, to be capable of causing injury.
6.4 Medication Non-Adherence
Medication adherence is a critical aspect of pharmacotherapeutic care that can be easily overlooked or underappreciated by healthcare providers. Non-adherence, also referred to as non-compliance, can be detrimental to patient care. It is important to remember that non-adherence may not be intentional.
Factors that can lead to medication non-adherence include:
· Complexity of medication regimens: When medication regimens are complex, patients may find it difficult to remember to take all their medications at the right time or in the correct way (e.g., with food).
· Side effects: Some medications can cause unpleasant side effects, which can lead a person to stop taking their medications. Some may believe that the benefits of the medication do not outweigh the side effects. Fear of side effects may also lead to non-adherence.
· Cost: Medications can be expensive, and some patients may not be able to afford the cost of their medications. This may include medications for which insurance companies or other payors have created administrative barriers to insurance coverage (e.g., prior authorization) to prevent inappropriate use.
· Lack of understanding or education: Individuals may not understand the importance of their medications or how to take them properly.
· Mental health or cognitive issues : Patients with mental health or cognitive issues may have difficulty remembering to take their medications, understanding the importance of their medications, or unable to follow complex instructions.
· Lack of social support : Patients who lack social support may have difficulty adhering to their medication regimens. They may not have anyone to remind them to take their medications or provide transportation to procure their prescriptions from a pharmacy.
· Cultural or language barriers : Patients from different cultures or with limited English proficiency may have difficulty understanding the instructions for their medications or may have beliefs that are not consistent with the medication regimen.
To promote medication adherence, clinicians should identify which of the above factor(s) may be contributing to non-adherence on a case-by-case basis, and work to resolve the root causes. For instance, if cost is a barrier, the provider may be able to help the patient enroll in a manufacturer support assistance program, or consider alternative therapies that may be available to the patient at a lower cost.
This chapter titled Unintended Medication Outcomes is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Karen Vuckovic from Introduction to Pharmacology by Carl Rosow, David Standaert, & Gary Strichartz ( MIT OpenCourseWare ) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.