Identifying Factors That Cause Pharmacy ErrorsLawCE

Release Date: December 1, 2008

Expiration Date: December 31, 2010


Gerald Gianutsos, PhD, JD
Associate Professor of Pharmacology
University of Connecticut School of Pharmacy
Storrs, Connecticut


Dr. Gianutsos has no actual or potential conflict of interest in relation to this program.

U.S. Pharmacist does not view the existence of relationships as an implication of bias or that the value of the material is decreased. The content of the activity was planned to be balanced, objective, and scientifically rigorous. Occasionally, authors may express opinions that represent their own viewpoint. Conclusions drawn by participants should be derived from objective analysis of scientific data.


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Participants have an implied responsibility to use the newly acquired information to enhance patient outcomes and their own professional development. The information presented in this activity is not meant to serve as a guideline for patient management. Any procedures, medications, or other courses of diagnosis or treatment discussed or suggested in this activity should not be used by clinicians without evaluation of their patients’ conditions and possible contraindications or dangers in use, review of any applicable manufacturer’s product information, and comparison with recommendations of other authorities.


To provide pharmacists with an understanding of pharmacy dispensing errors, including causes, prevention, and the legal issues resulting from these errors.


After completing this program, participants will be able to:

  1. Describe the impact of medical errors on the health care system.*
  2. Identify the types of dispensing errors that may occur.*
  3. Recognize the leading causes of dispensing errors.*
  4. Discuss the legal risks, responsibilities, and potential disciplinary issues that arise from dispensing errors.*
  5. Implement strategies to reduce medication errors.

*Also applies to pharmacy technicians.

A undercover investigation recently televised by ABC News reported on errors committed at pharmacies in the United States.1 The report, Pharmacy Errors: Unreported Epidemic?, drew attention to a problem faced by many pharmacists today—the dangers associated with the proliferation of dispensing errors.

Millions of TV viewers in the U.S. witnessed the devastating consequences that are possible when pharmacists make errors, and they were left with the impression that the overworked pharmacist is prone to making mistakes—mistakes that are not only common, but systematically hidden from the public.

The general public is well aware that medical errors exist and has a genuine fear of mistakes affecting its well-being. According to a poll conducted by the National Patient Safety Foundation, 42% of respondents had been affected by a medical error, either personally or through a friend or relative, and 32% indicated that the error had a permanent negative effect on the patient’s health.2

Pharmacists are highly skilled professionals delivering essential health care, but mistakes by pharmacists and other health care professionals can occur with striking frequency. According to The Quality of Health Care in America Project, established by the National Academies’ Institute of Medicine (IOM), errors committed within the health care system have significant impact on patient safety and health care costs (TABLE 1).3 According to their report, To Err is Human, the number of potential deaths due to medical errors each year may range as high as 98,000, which is greater than the number that occur from motor vehicle accidents, breast cancer, AIDS, or workplace accidents, respectively. Total annual costs related to medical errors, including health care and disability expenditures as well as lost income and productivity, are estimated at $37 to $50 billion, with preventable adverse events projected to run as high as $17 to $29 billion. Preventable medical errors are estimated to represent as much as 2% of total health care costs.3

Table 1
Impact of Medical Errors in the U.S.
Estimated annual deaths
Total annual costsa
Annual costs from preventable adverse events
Patient deaths due to medication errorsb
$37-$50 billion
$17-$29 billion
Inpatient: 1/854
Outpatient: 1/131

a Lost income, lost household productivity, disability, health care costs.
b Number of patient deaths attributed to medication errors.
Source: Reference 3.

Medication errors can occur anywhere within the system of drug prescribing, distribution, and administration, and may be due to a mistake by a pharmacist, physician, nurse, or other medical personnel. This lesson will review the available information on drug-related medical errors, with an emphasis on pharmacist errors, and will discuss the regulatory and practical approaches to reducing the number and impact of such errors.


The IOM report noted that deaths from medication errors increased 2.5-fold in inpatient settings between 1983 and 1993 and increased almost 8.5-fold in outpatient settings, suggesting that the use of the term “epidemic” may not be hyperbole.3 The general public is aware of the problem of errors and recognizes the risks. The results of a survey conducted by the American Society of Health-System Pharmacists found that Americans are “very concerned” about being given the wrong medicine (61%) and receiving two or more medicines that interact in a negative way (58%).2 Surprisingly, these concerns over incorrect drugs outweighed the frequency of concern over complications from a medical procedure (56%).2

Unfortunately, the public has ample reason for concern. One study reported that U.S. fatalities from acknowledged prescription errors increased by 243% between 1983 and 1998 to almost 10,000.4 This percentage increase was greater than for almost any other cause of death and far outpaced the increase in the number of prescriptions.4

Among physicians, the most common errors were inappropriate dosing, prescribing the wrong medication, and failure to monitor for side effects.5,6

In a long-term study at a teaching hospital, the most common types of prescribing errors were dosing errors, prescribing medications to which the patient was allergic, and prescribing inappropriate dosage forms.7 Data reported from U.S. hospitals indicate that 11% to 17% of medication errors were due to improper dispensing.8

In the hospital setting, adverse drug events (ADEs) are a significant economic and health risk. ADEs are usually considered to have several components, including outright mistakes, drug interactions, and unpredictable side effects, and are estimated to result in over 750,000 injuries and deaths each year, with excess costs of as much as $5.6 million for a large hospital.9 Incidence rates of ADEs vary from two to seven per 100 admissions among the hospitals that have conducted ADE studies.

Patients who experienced ADEs were hospitalized an average of eight to 12 days longer than patients who did not suffer ADEs, with their hospitalization costing $16,000 to $24,000 more.9 The majority of errors occurred during the ordering and administration stages.

While mistakes by pharmacists are a contributing factor to medical errors, these observations suggest the possibility that greater involvement by pharmacists in drug therapy review may also reduce the total number of prescription errors. In a study conducted at Brigham and Women’s Hospital, the ADE rate in its intensive care unit (ICU) was reduced from 33.0 per 1,000 patient days to 11.6 per 1,000 patient days by having a pharmacist participate in patient rounds with the ICU team.9

Among pharmacists, an error can also take many forms. Abood has classified pharmacists’ errors as mechanical or judgmental.5 A mechanical error is an error in the preparation and processing of the prescription, while a judgmental error is one of discretion in counseling, screening, or patient drug monitoring. Mechanical errors include dispensing the wrong drug, dosage form, directions, quantity, or strength or dose. Judgmental errors include improper or no counseling, failure to detect drug interactions, and inadequate drug use review. The most common error reported is the selection of the wrong drug. While errors may not always have severe consequences, studies have concluded that up to 3% of dispensing errors by inpatient hospital pharmacies are potentially serious.10

An analysis of malpractice claims against pharmacists found that mechanical errors accounted for 86% of liability claims.11 By far the most common type of error in malpractice litigation is the allegation that the wrong drug was dispensed (52%).11 These claims are responsible for the most serious patient injury and, when proven, result in the largest damage awards. Other significant mechanical error claims in malpractice litigation are dispensing the wrong dose of the correct drug and providing incorrect directions on the label. The reasons for errors will be discussed later, but outright mistakes resulting from overwork and distractions are exacerbated by confusion over similar drug names and illegible handwriting on written prescriptions. The most common intellectual error is derived from a failure to counsel. It should be noted that these are results of an analysis of liability claims and may not be representative of other possibly more common errors, which result in comparatively less severe injury that does not result in a liability claim. It is also a reasonable expectation that as pharmacists take on expanded roles in drug therapy management, the proportion of judgmental errors will rise.

While the number of misfilled prescriptions is not precisely known, several studies have attempted to examine the rate of errors in pharmacies. Studies using different methodologies have estimated dispensing error rates in ambulatory settings ranging from 1% to 24% of prescriptions.12 In one early study of a high-volume hospital outpatient pharmacy conducted in 1983, an audit revealed a dispensing error rate of 12.4%.13

In a nationwide survey of 1,000 community pharmacists conducted in 1996, more than half of the pharmacists reported making a dispensing error in the previous 60 days.14 The typical retail pharmacist admitted to making an average of 2.5 errors during the previous two-month period, and 8% believed that they made more than six. About one in four pharmacists believed that his or her error rate had increased during the previous year. More than half of the pharmacists reported that they dispensed the wrong dose, and more than 25% reported that they dispensed the wrong drug. Failure to catch drug interactions and contraindications or warn of potential hazards was much less common, reported by only about 2% of the respondents. Interestingly, workload and/or setting appeared to have an influence—47% of pharmacists dispensing fewer than 100 prescriptions per day reported making an error, while 60% of those dispensing 100 or more prescriptions per day were aware of a mistake. Among independent pharmacists, about half caught the error themselves, with 38% caught by the patient or family member. Among chain store pharmacists, only 26% caught the error themselves, with 68% being discovered by the patient.14

An investigation by a Boston newspaper of 51 Massachusetts pharmacies in 1999 revealed that 4% of prescriptions dispensed by community pharmacists contained errors; 88% of these involved the wrong drug or strength.15

In a more controlled study in which pharmacists recorded errors that they detected, the error rate was approximately 7.4% of all prescriptions.16 In this study, the errors were detected, so they could have been corrected before reaching the intended user, indicating that this measure overestimates the number of errors causing real harm to the patient. However, this can serve as a guideline for the potential scope of the problem, and it highlights the need for pharmacists to check their work and the work of technicians. The author estimates that one error gets past the normal verification process for each six errors that are detected, suggesting that potentially harmful error rates still exceed 1%.16

A systematic observational analysis of pharmacies (independent, chain, and health-system pharmacies) in six cities (Chicago, Los Angeles, Dallas-Fort Worth, Philadelphia, Seattle, Tampa) revealed an error rate of 1.7%, consistent with other less well-controlled studies.17 No difference in the error rate was observed among the three practice settings (i.e., chain, independent, health system). This is about four errors per day in a pharmacy with a daily volume of 250 prescriptions. Extrapolating these results to the U.S. as a whole, the authors estimate that there may be as many as 51.5 million errors in the 3 billion prescriptions filled annually. The observers categorized 6.5% of the errors as clinically significant, with the potential for 3.3 million important errors in the U.S. annually.17


Pharmacists generally believe that the risk of dispensing errors is increasing. In one survey, this view was held by 82% of pharmacists.18 A number of reasons for errors are cited by pharmacists in surveys and studies designed to examine the causes of errors, including high prescription volume, distractions, shortage of support personnel, look-alike/sound-alike drug names, inadequate opportunity to counsel, illegible handwriting, and fatigue. It is well known that the volume of prescriptions has been on an upswing for more than a decade. In 2000, 2.9 billion retail prescriptions were filled in the U.S., up 62% from a decade earlier.4 In 2005, 3.6 billion outpatient prescriptions were dispensed; this is an increase of 71% from 2.1 billion in 1994, compared with a population growth of only 9% over the same period.19 If, as pharmacists believe, error rates are indeed increasing at the same time that the number of prescriptions dispensed is rising, the potential risk to the public is alarming.

A study released by the Pharmacy Manpower Project showed that the workload for America’s pharmacists increased measurably between 2000 and 2004, and many practitioners believed that patient care could suffer as a result. A perception that the growing workload has negatively affected their ability to reduce medication errors was cited by 36% of the pharmacists surveyed in the study.20

It is not surprising that among pharmacists, factors that are believed to contribute to errors include high prescription volume, fatigue, overwork, interruptions, similar or confusing drug names, poor handwriting, and insufficient time for counseling.18 High prescription volume was named by 84% of the surveyed employee pharmacists, with overwork and fatigue named by 80%. Thus, pharmacists believe that the workplace environment contributes heavily to the occurrence of errors. Interestingly, another study examining death certificates in the U.S. found that medication error death rates spiked by 25% above normal at the beginning of each month.21 Although the reasons for the spike are unknown, the authors speculated that one cause could be increased pharmacy error rates due to increased dispensing volume at the beginning of the month.

The enormous increase in prescription volume places added stress on the pharmacist and is further magnified by the nationwide shortage of pharmacists. In a more detailed example, results from a University of North Carolina study indicated that the average retail pharmacist’s workload increased by 57% between 1991 and 2000, such that the typical pharmacist filled a prescription an average of every five minutes compared with every eight minutes in 1991.22 In part, the increase was due to an expansion of the over-65 population with the accompanying increased need for prescription medications.

When pharmacists were asked what they perceived to be a safe number of prescriptions that could be dispensed by or in the presence of a single pharmacist in a work day, they responded with a median value of 150 or 17 per hour.18 Moreover, 58% agreed that a regulatory guideline for a maximum safe dispensing load should be enacted, a step that several states have considered taking. Other health professionals are also affected by working conditions, and regulatory agencies have responded to these concerns by regulating the workplace. For example, the risk of 30-day mortality increases as the patient-to-nurse ratio increases, resulting in some states dictating a maximum patient-to-nurse ratio.23

Many pharmacists intuitively believe that job stress can have a deleterious effect on their performance. One analysis of stress has suggested that it may have four different adverse effects on the cognitive system, which may increase error rates and interfere with error detection.16 Stress may increase the rate of information processing and may lead to exceeding the optimal capacity for processing information. Thinking about stressful events may distract attention away from critical tasks. Stress may lead to alterations in work patterns and shortcuts that may promote inaccurate behavior. Stress may also cause cognitive systems to default to responses that emphasize past habits instead of recently learned adaptive strategies.

In addition to contributing to dispensing errors, an increased workload also increases the likelihood of dispensing a medication that could cause a drug–drug interaction. A survey of pharmacists in 18 metropolitan areas revealed that drug–drug interactions increased with pharmacy or pharmacist workload, increasing by approximately 3% for each additional prescription dispensed per hour.24 The authors attributed this to a reduction in the time available to assess potential interactions.

The relationship between workload and errors is not simple. Some studies have failed to show a correlation between higher workload and higher error rates. One study failed to find an association between the rate of potentially serious errors and increasing work volume in a high-volume, hospital-based, outpatient pharmacy.25 Nevertheless, this study detected variations in the error frequency depending on the time of day, with peak error occurrence noted during the lunch hour and the hour before closing.

In another research report, pharmacists were found to be most vulnerable to making an error when they were less busy, or during a dramatic shift in the number of prescriptions presented (i.e., going from high to low and vice versa).16 This was especially prevalent in high-volume settings. One explanation provided is that when pharmacists are especially busy, their mental faculties are highly engaged, and they are very focused on their tasks. During slower periods, boredom may contribute to lack of attention and more errors. The author emphasized that workload alone could not predict a pharmacist’s performance, although he acknowledged that working at a faster pace increases job-related tension. The author concluded that the quality of a pharmacist’s performance was also determined by personal attributes, such as how the pharmacist perceived and responded to workload conditions. Pharmacists who were more satisfied with their jobs and the quality of their breaks made fewer errors even though they filled more prescriptions per hour than those who were less satisfied. Other sources of stress also contributed to errors. For example, pharmacists who reported high levels of stress in dealing with third-party payers made more errors than those reporting less stress.

Other factors in addition to sheer workload volume have an impact on errors. The Massachusetts Board of Registration in Pharmacy conducted a retrospective pilot study in an attempt to identify causative factors associated with medication errors.26 The study revealed that pharmacists perceive a number of different elements as causative factors for medication errors (TABLE 2)

Table 2
Most Common Causes of
Errors Cited By Pharmacists
  • Too many telephone calls (62%)
  • Overload/unusually busy day (59%)
  • Too many customers (53%)
  • Lack of concentration (41%)
  • No one available to double-check (41%)
  • Staff shortage (32%)
  • Similar drug names (29%)
  • No time to counsel (29%)
  • Illegible prescription (26%)
  • Misinterpreted prescription (24%)

Source: Reference 26.

The Massachusetts experience highlighted the contribution of distractions and interruptions to errors. In an observational study of an ambulatory clinic, pharmacists and technicians were subjected to an average of more than six distractions and interruptions per hour, which resulted in a higher volume of errors.12 One author advocates minimizing distractions and interruptions by removing extraneous material from the workspace and requesting that personnel and patients do not interrupt the pharmacist while he or she is in the middle of a task.16

In addition to the work environment, another important source of errors is the similarity in drug names. A busy pharmacist can easily substitute the wrong drug for one with a similar name when reading an illegible prescription, receiving a prescription over the phone, or simply picking up the wrong or adjacent bottle from the shelf. Look-alike/sound-alike drugs exist between brand names of different drugs, generic names of different drugs, or between a brand and a generic name. The U.S. Pharmacopeia’s (USP) data reporting program (MEDMARX) reported that more than 1,400 commonly used drugs are involved in errors linked to drug names that look alike or sound alike, including all of the 10 most commonly prescribed drugs. Data compiled over a three-year period indicated that 1.4% of the errors resulted in patient harm, including seven errors that may have caused or contributed to patient deaths.27


The apparent proliferation of errors by pharmacists has not gone unnoticed. Both regulatory agencies and patients have taken steps to seek redress for harm caused by mistakes. Pharmacists may be legally liable for their errors. In fact, the number of legal and administrative actions filed against pharmacist has risen significantly as the frequency of errors increases. As a consequence of their errors, pharmacists may face lawsuits from patients resulting in monetary damage awards and/or actions by regulatory agencies that place their professional licensure in jeopardy.

Malpracti/USPExams/Civil Liability: No health care professional wants to make a mistake, especially one that can result in patient injury with devastating consequences. Pharmacists are aware that their missteps can result in minor harm, debilitating injuries, and even death. However, beyond any personal feelings of guilt or embarrassment, pharmacists, like other professionals, are at risk for legal actions for their errors, and lawsuits have proliferated along with errors. Pharmacist and attorney Jesse C. Vivian noted, “Ten years ago, you have about 15 to 20 [malpractice] cases at the appellate level. Today, you see 15 cases a month.”28

These legal entanglements can result in substantial damage awards. For example, in one recent case, a pharmacist dispensed glipizide, a sulfonylurea, instead of a drug for gout; the patient went into a coma and eventually suffered a stroke and died. The pharmacy chain that employed the pharmacist was ordered to pay the patient’s estate $31.3 million.29 In another case, a patient mistakenly received a dose of warfarin that was 10 times too high, resulting in cerebral hemorrhage and death; the family received a damage award of $25.8 million.30

Pharmacists are liable for their mistakes under the theory of negligence. A complete discussion of malpractice and negligence liability is beyond the scope of this lesson (see Reference 31 for an expanded discussion). Generally, pharmacists are allowed no margin for mechanical errors. Pharmacists have a legal duty to provide patients with the best care possible. Drugs have the potential to produce serious harm when used improperly, and patients ordinarily are unable to appreciate the potential harm; they therefore rely on the pharmacist’s skill and knowledge. A pharmacist would be liable if he or she breached that duty in a manner that caused harm to the patient. By tradition, courts long ago established that the pharmacist has a legal responsibility to take extreme care to dispense the correct medication, supply the correct dose, and provide the correct label instructions. These legal responsibilities, of course, mirror the traditional role for the pharmacist but also represent the most common source of pharmacist errors.

Significantly, the concept of the pharmacist’s legal duty is expanding to cover emerging duties for pharmacists beyond the duty to dispense the proper drug, to include failure to warn of or detect adverse patient outcomes and the duty to counsel.31 As pharmacists assume a greater role in patient drug therapy management, the opportunity for mistakes increases and the risk of liability also increases. By taking on increasing discretionary and decision-making functions, the pharmacist runs the risk of being held liable for mistakes in judgment and would no longer be shielded by the liability of the physician. Guided by the mandates of the Omnibus Budget Reconciliation Act of 1990 (OBRA 90) and other changes in the concept of pharmacy care, it is no longer sufficient for pharmacists to be technically accurate; courts are increasingly recognizing the specialized knowledge of pharmacists and expecting pharmacists to demonstrate that knowledge.

Regulatory Responses: Pharmacists are not only legally liable to the patient who was harmed by their error, but they may also be subject to regulatory actions by their state pharmacy commission. Such actions may result in penalties including suspension or revocation of a pharmacist’s license. Some states have suspended pharmacists for a single prescription error.4

For example, in Massachusetts, the number of disciplinary actions against pharmacists and technicians increased from 30 in 2004 to 49 in 2005, while Georgia saw a 40% increase in consumer complaints about dispensing errors in one year.32 These data strongly suggest that nationwide, pharmacists are at an increasingly greater risk of being involved not only in a lawsuit but also in a disciplinary action.

In at least two states, Georgia and South Carolina, consumers can conduct a search to verify the current licen-sure status of a pharmacy or pharmacist and whether the state board has taken disciplinary action against them. In Georgia, consumers searching on the secretary of state’s Web site ( will have the capability of determining why a disciplinary action was taken. In South Carolina, the relevant site is the Division of Professional and Occupational Licensing ( The public appears to be supportive of further regulatory measures, believing that medical errors are the result of the failures of individual providers. When asked in a survey about possible solutions to medical errors, 75% of respondents thought it would be most effective to keep health professionals with bad track records from providing care, and 69% thought the problem could be solved through better training of health professionals.2

Not all responses by regulatory agencies, however, involve punitive actions against pharmacists. Other types of approaches designed to reduce the future occurrence of errors have also become common. For example, most states have begun to enact mandated quality control and error reporting measures.33 In Connecticut, pharmacies must display a conspicuous sign providing information to patients on reporting suspected errors to the Department of Consumer Protection, the agency that oversees pharmacies in this state. In addition, pharmacies must perform a quality assurance review within two days of discovering an error that includes considering recommendations for changes in the pharmacy’s policies or procedures to minimize errors, and they must make the records available for inspection by the pharmacy commission.34 In Massachusetts, pharmacists must investigate medication errors, record them with their pharmacies, notify patients, and undergo yearly antiprescription-error training.35 Two states, New York and Florida, require pharmacists to obtain continuing education credits specific to medication errors.36,37

Pharmacy boards in at least three states—California, Wyoming, and Oregon—have taken the step of instituting regulations mandating that prescription bottle labels include the color and shape of the tablets or capsules, and any identification code appearing on them.38 Thus, the pharmacist or technician conducting a check or a counseling session can more easily detect that an error has occurred by comparing the label with the contents of the bottle and take corrective action to avoid harm, while the alert patient has the ability to minimize harm by questioning a drug that does not match the description.

Nationally, reporting systems exist which also help to analyze and prevent prescription errors. One such program is MEDMARX, an anonymous, Internet-accessible program operated by the USP and used by hospitals and related institutions nationwide to report, track, and analyze medication errors.27 Since its inception in 1998, MEDMARX has received more than 1.2 million reports of medication errors from more than 870 health care facilities across the U.S. The USP also operates a Medication Errors Reporting Program in conjunction with the Institute for Safe Medication Practices (ISMP). Health care professionals who encounter actual or potential medication errors may report them confidentially and anonymously through a secure online form. Among the types of errors reported are misinterpretations, miscalculations, misadministrations, difficulty in interpreting handwritten orders, and misunderstanding of verbal orders. The USP reports on the data collected annually, reviews each medication error report it receives for health hazards, and forwards all information to the FDA and the product manufacturer as part of the FDA’s MedWatch program.

A few states have begun to address the issue of excessive workload and its impact on errors. Recommendations have taken a number of different approaches. One recent proposal calls for an increase in the number of days’ supply allowed for Medicaid-covered prescriptions from 30 days to 100 days to reduce the number of times people need to refill prescriptions.22 A rule enacted in North Carolina states that employers cannot require pharmacists to work more than 12 continuous hours per day. If a pharmacist works for eight continuous hours, the rule states that the employer must offer the pharmacist the opportunity to take one 30-minute meal break and one additional 15-minute break during the shift.39 Employers who violate the rule may be sanctioned by the pharmacy board. During the rulemaking process, pharmacists commented on being overworked and pressured in a manner that jeopardized public safety. Nevada and West Virginia have similar rules, and other states have also considered enacting like measures. The California Pharmacists Association proposed a similar contract calling for a rest break every three to four hours.4 The Arizona State Board of Pharmacy endorsed a proposal that would encourage pharmacy owners and managers to allow pharmacy personnel to “close and secure” (in compliance with board rules) a pharmacy for a maximum of 30 minutes at midshift, allowing personnel to relax, have a meal, or otherwise occupy themselves.40

Other workplace standards for employee pharmacists have been proposed. Among the suggested guidelines: providing a rest break every two to three hours, restricting the length of the workweek (e.g., 108 hours every two weeks), and dispensing an average of no more than a certain number of prescriptions per hour per pharmacist. Some states have considered enacting regulations that limit the number of prescriptions a pharmacist may fill during a shift. Through a new regulation, the North Carolina board set 150 prescriptions per pharmacist per day as the limit for safe prescription dispensing.39 Any pharmacy dispensing more than this limit could be subject to disciplinary action should a medication error occur. Iowa has set a guideline of not more than 14.2 prescriptions an hour per pharmacist.4 The California Pharmacists Association proposed contract requested that pharmacists not routinely dispense more than an average of 15 prescriptions per hour.4 It is not unreasonable to expect that more states will examine workplace issues and seek to reduce errors—and protect the public—through regulatory guidelines.

What about pharmacists who are overly stressed by the seemingly ever-increasing prescription volume? Pharmacists need to be aware that workload issues are not a defense against liability for dispensing errors, and recent regulatory changes noted above may actually increase their liability. Moreover, an alert plaintiff may use excessive workload as an argument to support a negligence claim in the case of an error.


Clearly, errors can have serious consequences for the patient and for the pharmacist who commits them. The prudent pharmacist would be well advised to institute quality-control measures where possible to reduce the likelihood that errors will occur.

Baker and Mondt advocate the use of a “triple check plus two” system.11 In this system, the medication is checked three times: when it is taken off the shelf, when it is placed in the container, and when the order is filled. In addition, the National Drug Code (NDC) number in the computer system should be checked against the prescription bottle, and the prescription should be checked again during counseling.

Counseling provides many benefits to the patient and is also a particularly effective measure in reducing errors. Many errors (e.g., wrong drug) are detected during a counseling session. One estimate from North Carolina suggests that half of medication-related deaths could have been prevented by appropriate and timely counseling.5 Abood recommends a “show and tell” technique in which the patient is shown the drug while the pharmacist asks three key questions5: 1) What did the physician tell you the drug is for?; 2) How were you told to take the medication?; and 3) What directions did the physician provide for taking the medication? The pharmacist can then compare this information with the drug and label and recognize discrepancies. In the hospital setting, at least one study concluded that errors could be reduced by expanded clinical pharmacy services, including pharmacist-provided admission history and drug protocol management.41

Errors can also be prevented by reducing pharmacist stress and patient pressure, including providing a comfortable waiting area.5 Other recommendations include not storing drugs with similar names near each other, specifically identifying and segregating drugs that have a non-oral route of administration, circling the number of tablets in a bottle if different from 100, and taking the prescription or label to the shelf when retrieving the drug instead of relying on recall.5,17

Pharmacists may also utilize existing resources for guidance in minimizing errors. One valuable resource for pharmacists is the ISMP. The ISMP Web site ( includes lists of confused drug names, error-prone abbreviations, high-alert medications, and other useful information. The Agency for Healthcare Research and Quality ( offers quality measures and patient safety information.

The FDA’s Role: The FDA also works with manufacturers to reduce errors.42 Some recent program enactments include:

  1. a rule enacted in 2002 to require bar codes on certain drugs and biological product labels, which would permit automated scanning equipment to read the labels;
  2. improved error tracking and reporting mechanisms; and
  3. standardized drug facts labels on OTC products to reduce consumer confusion.

The FDA is also working to reduce confusion due to similar drug names.42 The FDA reviews about 300 drug names a year before they are marketed and rejects about one-third of the names that drug companies propose. The agency also tests drug names with the help of health professionals who volunteer to simulate real-life drug order situations. The FDA is also developing a computerized program that will permit a more scientific approach to comparing names.

After drugs are approved, the FDA tracks reports of errors due to drug name confusion and informs health professionals of problems.42 As an example, the FDA cites the inadvertent administration of methadone rather than the intended Metadate ER (methylphenidate) for the treatment of attention-deficit/hyperactivity disorder. Some other examples of documented confusion from the FDA include: Serzone (nefazodone) and Seroquel (quetiapine); Lamictal (lamotrigine) and Lamisil (terbinafine); Taxotere (docetaxel) and Taxol (paclitaxel); Zantac (ranitidine), Zyrtec (cetirizine), and Zyprexa (olanzapine); and Celebrex (celecoxib) and Celexa (citalopram). In 1994, the FDA changed a drug name after it was approved when the thyroid medicine Levoxine (levothyroxine) was being confused with the heart medicine Lanoxin (digoxin). The agency indicates that it has not received reports of errors due to confusion since the brand name was changed to Levoxyl.

The FDA’s Office of Generic Drugs has also instituted several error reduction programs.42 These include a program to eliminate the use of error-prone abbreviations and a name differentiation project to reduce the confusion caused by look- or sound-alike drug names. The name differentiation project encourages the use of “tall man” lettering on drug labels in which the name is visually differentiated by the use of distinguishing emphasis (e.g., ClomiPHENE and ClomiPRAMINE) and the use of italics, underscores, and color.

Some other FDA recommendations regarding drug name confusion include encouraging pharmacists to separate similar drug products on pharmacy shelves and encouraging physicians to indicate both brand and generic drug names on prescription orders, as well as the drug’s indication, which provides the pharmacist with several cues to prevent confusion. Other recommendations include the elimination of handwritten prescriptions to avoid problems associated with illegible or ambiguous handwriting.


A medical error that culminates in serious injury or death is a health practitioner’s worst nightmare. Despite best efforts, some errors are inevitable. Nevertheless, pharmacists need to be able to identify workplace pressures and other factors that lead to dispensing errors, take appropriate steps to minimize the occurrence of errors, and develop systems and policies to enhance patient safety. These actions should include proper training and supervision of employees, proper documentation and quality control efforts, maintenance of adequate levels of personnel, and efforts to promote counseling. Attempts to hide or ignore errors can lead to more disastrous consequences.

Pharmacists need to keep abreast of changes in regulations that can affect the reporting, documentation, and prevention of errors, as well as mandated changes in the workplace environment. As they are pressured to fill an ever-growing number of prescriptions, pharmacists should remember that the consequences of errors not only lead to legal complications involving large damage awards and disciplinary actions but also contribute to diminished patient welfare, loss of life, and increased health care costs. As the IOM summary concluded: “It may be part of human nature to err, but it is also part of human nature to create solutions, find better alternatives, and meet the challenges ahead.”3 Pharmacists must be up to the challenge.


  1. U.S. pharmacy errors: unreported epidemic? ABC News. Aired March 29, 2007. Accessed October 1, 2008.
  2. Medical Errors: The Scope of the Problem. Fact sheet. Rockville, MD: Agency for Healthcare Research and Quality; 2000. Publication No. AHRQ 00-P037. Accessed October 1, 2008.
  3. Kohn LT, Corrigan JM, Donaldson MS, eds. To Err Is Human: Building a Safer Health System. Washington, DC: National Academy Press; 2000.
  4. Phillips DP, Bredder CC. Morbidity and mortality from medical errors: an increasingly serious public health problem. Annu Rev Public Health. 2002;23:135-150.
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