The goal of drug therapy is the achievement of defined therapeutic outcomes that improve a patient’s quality of life while minimizing patient risk.1 There are inherent risks, both known and unknown, associated with the therapeutic use of drugs (prescription and nonprescription) and drug administration devices. The incidents or hazards that result from such risk have been defined as drug misadventuring, which includes both adverse drug reactions (ADRs) and medication errors.2 This document addresses medication errors—episodes in drug misadventuring that should be preventable through effective systems controls involving pharmacists, physicians and other prescribers, nurses, risk management personnel, legal counsel, administrators, patients, and others in the organizational setting, as well as regulatory agencies and the pharmaceutical industry.
This document suggests medication error prevention approaches that should be considered in the development of organizational systems and discusses methods of managing medication errors once they have occurred. These guidelines are primarily intended to apply to the inpatient hospital setting because of the special collaborative processes established in the setting [e.g., formulary system, pharmacy and therapeutics (P&T) committee, and opportunity for increased interaction among health-care providers].
Recommendations for practice settings other than hospitals are beyond the scope of this document, although many of the ideas and principles may be applicable.
Medication errors compromise patient confidence in the health-care system and increase health-care costs. The problems and sources of medication errors are multidisciplinary and multifactorial. Errors occur from lack of knowledge, substandard performance and mental lapses, or defects or failures in systems.3,4 Medication errors may be committed by both experienced and inexperienced staff, including pharmacists, physicians, nurses, supportive personnel (e.g., pharmacy technicians), students, clerical staff (e.g., ward clerks), administrators, pharmaceutical manufacturers, patients and their caregivers, and others. The incidence of medication errors is indeterminate; valid comparisons of different studies on medication errors are extremely difficult because of differences in variables, measurements, populations, and methods.2
Many medication errors are probably undetected. The outcome(s) or clinical significance of many medication errors may be minimal, with few or no consequences that adversely affect a patient. Tragically, however, some medication errors result in serious patient morbidity or mortality.3 Thus, medication errors must not be taken lightly, and effective systems for ordering, dispensing, and administering medications should be established with safeguards to prevent the occurrence of errors. These systems should involve adequately trained and supervised personnel, adequate communications, reasonable workloads, effective drug handling systems, multiple procedural and final product checks by separate individuals, quality management, and adequate facilities, equipment, and supplies.
The pharmacist’s mission is to help ensure that patients make the best use of medications.5 This applies to all drugs used by inpatients or ambulatory patients, including oral or injectable products, radiopharmaceuticals, radiopaque contrast media, anesthetic gases, blood-fraction drugs, dialysis fluids, respiratory therapy agents, investigational drugs, drug samples, drugs brought into the hospital setting by patients, and other chemical or biological substances administered to patients to evoke a pharmacological response.6
Through a systems-oriented approach, the pharmacist should lead collaborative, multidisciplinary efforts to prevent, detect, and resolve drug-related problems that can result in patient harm.1 An understanding of the risk factors associated with medication errors should enable improved monitoring of patients and medications associated with increased risk for serious errors and should enable the development of organizational systems designed to minimize risk.7 The pharmacist should participate in appropriate organizational committees and work with physicians, nurses, administrators, and others to examine and improve systems to ensure that medication processes are safe.
Types of Medication Errors
Medication errors include prescribing errors, dispensing errors, medication administration errors, and patient compliance errors. Specific types of medication errors are categorized in Table 1, based on a compilation of the literature.3,7–18
Types of Medication Errors3,7–18,a
Incorrect drug selection (based on indications, contraindications, known allergies, existing drug therapy, and other factors), dose, dosage form, quantity, route, concentration, rate of administration, or instructions for use of a drug product ordered or authorized by physician (or other legitimate prescriber); illegible prescriptions or medication orders that lead to errors that reach the patient
The failure to administer an ordered dose to a patient before the next scheduled dose, if any
Wrong time error
Administration of medication outside a predefined time interval from its scheduled administration time (this interval should be established by each individual health care facility)
Unauthorized drug errorc
Administration to the patient of medication not authorized by a legitimate prescriber for the patient
Improper dose errord
Administration to the patient of a dose that is greater than or less than the amount ordered by the prescriber or administration of duplicate doses to the patient, i.e., one or more dosage units in addition to those that were ordered
Wrong dosage-form errore
Administration to the patient of a drug product in a different dosage form than ordered by the prescriber
Wrong drug-preparation errorf
Drug product incorrectly formulated or manipulated before administration
Wrong administration-technique errorg
Inappropriate procedure or improper technique in the administration of a drug
Deteriorated drug errorh
Administration of a drug that has expired or for which the physical or chemical dosage-form integrity has been compromised
Failure to review a prescribed regimen for appropriateness and detection of problems, or failure to use appropriate clinical or laboratory data for adequate assessment of patient response to prescribed therapy
Inappropriate patient behavior regarding adherence to a prescribed medication regimen
Other medication error
Any medication error that does not fall into one of above predefined categories
a The categories may not be mutually exclusive because of the multidisciplinary and multifactorial nature of medication errors.
b Assumes no prescribing error. Excluded would be (1) a patient’s refusal to take the medication or (2) a decision not to administer the dose because of recognized contraindications. If an explanation for the omission is apparent (e.g., patient was away from nursing unit for tests or medication was not available), that reason should be documented in the appropriate records.
c This would include, for example, a wrong drug, a dose given to the wrong patient, unordered drugs, and doses given outside a stated set of clinical guidelines or protocols.
d Excluded would be (1) allowable deviations based on preset ranges established by individual health care organizations in consideration of measuring devices routinely provided to those who administer drugs to patients (e.g., not administering a dose based on a patient’s measured temperature or blood glucose level) or other factors such as conversion of doses expressed in the apothecary system to the metric system and (2) topical dosage forms for which medication orders are not expressed quantitatively.
e Excluded would be accepted protocols (established by the pharmacy and therapeutics committee or its equivalent) that authorize pharmacists to dispense alternate dosage forms for patients with special needs (e.g., liquid formulations for patients with nasogastric tubes or those who have difficulty swallowing), as allowed by state regulations.
f This would include, for example, incorrect dilution or reconstitution, mixing drugs that are physically or chemically incompatible, and inadequate product packaging.
g This would include doses administered (1) via the wrong route (different from the route prescribed), (2) via the correct route but at the wrong site (e.g., left eye instead of right), and (3) at the wrong rate of administration.
h This would include, for example, administration of expired drugs and improperly stored drugs.
A potential error is a mistake in prescribing, dispensing, or planned medication administration that is detected and corrected through intervention (by another health-care provider or patient) before actual medication administration. Potential errors should be reviewed and tabulated as separate events from errors of occurrence (errors that actually reach patients) to identify opportunities to correct problems in the medication use system even before they occur. Detection of potential errors should be a component of the hospital’s routine quality improvement process. Documentation of instances in which an individual has prevented the occurrence of a medication error will help identify system weaknesses and will reinforce the importance of multiple checks in the medication use system.
Recommendations for Preventing Medication Errors
Organizational systems for ordering, dispensing, and administering medications should be designed to minimize error. Medication errors may involve process breakdowns in more than one aspect of a system. This section provides recommendations to the management staff (general and departmental) of hospitals, as well as to individual prescribers, pharmacists, nurses, patients, pharmaceutical manufacturers, and others.
Organizational and Departmental Recommendations. Organizational policies and procedures should be established to prevent medication errors. Development of the policies and procedures should involve multiple departments, including pharmacy, medicine, nursing, risk management, legal counsel, and organizational administration. The following recommendations are offered for organizational management and clinical staff: 3,8,11–14,16,19–29
- Using the principles of the formulary system, the P&T committee (or its equivalent)—composed of pharmacists, physicians, nurses, and other health professionals—should be responsible for formulating policies regarding the evaluation, selection, and therapeutic use of drugs in organized health-care settings.
- Care and consideration must be given in hiring and assigning personnel involved in medication ordering, preparation, dispensing, administration, and patient education. Policies and procedures should be developed that ensure adequate personnel selection, training, supervision, and evaluation. This would include the need to ensure proper interviewing, orientation, evaluation of competency, supervision, and opportunities for continuing professional and technical education.
- Sufficient personnel must be available to perform tasks adequately. Policies and procedures should ensure that reasonable workload levels and working hours are established and rarely exceeded.
- Suitable work environments should exist for the preparation of drug products. Potential error sources within the work environment, such as frequent interruptions, should be identified and minimized.
- Lines of authority and areas of responsibility within the hospital should be clearly defined for medication ordering, dispensing, and administration. The system should ensure adequate written and oral communications among personnel involved in the medication use process to optimize therapeutic appropriateness and to enable medications to be prescribed, dispensed, and administered in a timely fashion. All systems should provide for review and verification of the prescriber’s original order (except in emergency situations) before a drug product is dispensed by a pharmacist. Any necessary clarifications or changes in a medication order must be resolved with the prescriber before a medication is administered to the patient. Written documentation of such consultations should be made in the patient’s medical record or other appropriate record. Nursing staff should be informed of any changes made in the medication order. Changes required to correct incorrect orders should be regarded as potential errors, assuming the changes occurred in time to prevent the error from reaching the patient.
- There should be an ongoing, systematic program of quality improvement and peer review with respect to the safe use of medications. A formal drug use evaluation (DUE) program, developed and conducted through collaborative efforts among medicine, pharmacy, and nursing, should be integrated and coordinated with the overall hospital quality improvement program. To prevent medication errors, a portion of the DUE program should focus on monitoring the appropriate use of any drugs associated with a high frequency of adverse events, including specific drug classes (such as antimicrobials, antineoplastic agents, and cardiovascular drugs) and injectable dosage forms (e.g., potassium products, narcotic substances, heparin, lidocaine, procainamide, magnesium sulfate, and insulin). The quality improvement program should include a system for monitoring, reviewing, and reporting medication errors to assist in identifying and eliminating causes of errors (system breakdowns) and preventing their recurrence. Table 2 lists common causes of medication errors, i.e., areas where there may be system breakdowns.
Common Causes of Medication Errors
Ambiguous strength designation on labels or in packaging
Drug product nomenclature (look-alike or sound-alike names, use of lettered or numbered prefixes and suffixes in drug names)
Equipment failure or malfunction
Inaccurate dosage calculation
Inadequately trained personnel
Inappropriate abbreviations used in prescribing
Lapses in individual performance
- Pharmacists and others responsible for processing drug orders should have routine access to appropriate clinical information about patients (including medication, allergy, and hypersensitivity profiles; diagnoses; pregnancy status; and laboratory values) to help evaluate the appropriateness of medication orders.
- Pharmacists should maintain medication profiles for all patients, both inpatients and ambulatory patients, who receive care at the hospital. This profile should include adequate information to allow monitoring of medication histories, allergies, diagnoses, potential drug interactions and ADRs, duplicate drug therapies, pertinent laboratory data, and other information.
- The pharmacy department must be responsible for the procurement, distribution, and control of all drugs used within the organization. Adequate hours for the provision of pharmaceutical services must be maintained; 24-hour pharmaceutical service is strongly recommended in hospital settings. In the absence of 24-hour pharmaceutical service, access to a limited supply of medications should be available to authorized nonpharmacists for use in initiating urgent medication orders. The list of medications to be supplied and the policies and procedures to be used (including subsequent review of all activity by a pharmacist) should be developed by the P&T committee (or its equivalent). Items should be chosen with safety in mind, limiting wherever possible medications, quantities, dosage forms, and container sizes that might endanger patients. The use of well-designed night cabinets, after-hours drug carts, and other methods would preclude the need for non-pharmacists to enter the pharmacy. Access to the pharmacy by nonpharmacists (e.g., nurses) for removal of doses is strongly discouraged; this practice should be minimized and eliminated to the fullest extent possible. When 24-hour pharmacy service is not feasible, a pharmacist must be available on an “on-call” basis.
- The pharmacy manager (or designee), with the assistance of the P&T committee (or its equivalent) and the department of nursing, should develop comprehensive policies and procedures that provide for efficient and safe distribution of all medications and related supplies to patients. For safety, the recommended method of distribution within the organized health-care setting is the unit dose drug distribution and control system.
- Except in emergency situations, all sterile and nonsterile drug products should be dispensed from the pharmacy department for individual patients. The storage of nonemergency floor stock medications on the nursing units or in patient-care areas should be minimized. Particular caution should be exercised with respect to drug products that have commonly been involved in serious medication errors or whose margin of safety is narrow, such as concentrated forms of drug products that are intended to be diluted into larger volumes (e.g., concentrated lidocaine and potassium chloride for injection concentrate). All drug storage areas should be routinely inspected by pharmacy personnel to ensure adequate product integrity and appropriate packaging, labeling, and storage. It is important that drug products and other products for external use be stored separately from drug products for internal use.
- The pharmacy director and staff must ensure that all drug products used in the organizational setting are of high quality and integrity. This would include, for example, (1) selecting multisource products supported by adequate bioavailability data and adequate product packaging and labeling, (2) maintaining an unexpired product inventory, and (3) keeping abreast of compendial requirements.
You may also need