Medication Adverse Events

Service: Risk Management
Subject: Care
Setting: Medications

Adverse medication events consist of both preventable medication incidents and adverse reactions (AHRQ, 2019). Medications are one of the most frequently cited sources of adverse events in all healthcare settings. Errors can occur at any or multiple points in the medication use process. Certain patient populations such as neonatal and paediatric patients, frail elderly or the critically ill are especially vulnerable to medication-related events. High-alert medications defined as drugs that bear a heightened risk of causing significant patient harm when used in error (such as insulin, opiates, Chemotherapy agents) require heightened vigilance during ordering, transcribing, dispensing, administering and monitoring (Institute for Safe Medication Practices Canada, 2019). In 2015, five pharmaceutical events identified as “patient safety incidents that result in serious patient harm or death that are preventable using organizational checks and balances”, aka “never events” (defined as “patient safety incidents that result in serious patient harm or death that are preventable using organizational checks and balances”, Canadian Patient Safety Institute and Health Quality Ontario, 2015).  

Common Claim Themes

Claims frequently involve:

  • High-alert medication errors.
  • Vulnerable patients (e.g., neonatal and paediatric, frail elderly and critically ill patients).


  • Cumbersome or impractical medication policies/procedures.
  • Assumption that medication administration and use of IV ‘smart pumps’ is a core competency of all nurses (including agency).
  • Lack of processes to ensure requested laboratory tests are performed and results reviewed prior to medication administration (e.g., electrolytes).
  • Laboratory calibration errors resulting in inaccurate results and inappropriate medication titration.
  • Inexperienced staff ordering, preparing or administering medications to unfamiliar patient populations (e.g., neonates) or with unfamiliar medication concentrations.
  • Work environments/workloads non-conducive to “independent double checks.”

Judgement and knowledge

  • Re-ordering of medications without re-assessment.
  • Failure to re-order medication(s) post procedures.
  • Failure to escalate concerns about an order with the prescribing clinician.
  • Incorrect programming of smart pumps.
  • Failure to carefully read manufacturers’ printed labels.

Documentation and communication

  • Inconsistent nursing documentation of patient assessments/vital signs before and after administration.
  • Failure to label syringes, vials, bowls, etc. for all topical and injectable medications in the operating room.
  • Illegible handwritten orders.

Case Study 1

A patient with a previous history of stroke and atrial fibrillation was admitted to the hospital with stroke-like symptoms. Pending the result of a computerized axial tomography (CT), the patient’s anti-coagulant, Coumadin, was discontinued with a plan to restart the medication at an increased dose if the scan was negative for internal bleeding. The Coumadin was not restarted until five days later, just prior to discharge. Two days following discharge, the patient suffered a massive blood clot in the legs and subsequently died. Experts concluded that the patient’s death was triggered by the delay in restarting the Coumadin.

Case Study 2

A patient with history of diabetes was admitted to ICU with differential diagnosis of hypoglycemia with concomitant seizures.   Blood sugars obtained by lab offered conflicting results demonstrating both hypoglycemia and hyperglycemia. Notwithstanding the discrepancy, measures were instituted to reduce the high result by employing an intensive insulin protocol which ultimately resulted in a critical insulin overdose.  Despite ongoing uncertainty regarding the conflicting low blood sugar results, staff failed to follow procedural protocol requiring monitoring of patient every 30 minutes. Patient sustained significant permanent neurological deficits due to insulin overdose.

Mitigation Strategies

Reliable Care Processes

  • Adopt standardized evidence-based dosing and monitoring guidelines for opioids, including (but not limited to) vulnerable and at-risk patients such as neonatal, paediatric, critically ill and frail elderly patients including initial and maximum dose recommendations.
  • Maintain an environment which supports a culture that fosters patient safety as a priority and supports questioning and challenging medication orders. 
  • Reconcile medications using a systematic and comprehensive review of all the medications a patient is taking, when patients are admitted, transferred and discharged.
  • Implement effective strategies to reduce distractions during medication preparation and administration.
  • Adopt a carefully selected, limited list of medications requiring independent double checks.
  • Adopt a standardized “Do Not Use” list for abbreviations, symbols and dosage designations.
  • Dispense high-alert medications in ready-to-use single doses, especially neonatal and paediatric patients; consider pharmacy preparation and dispensing of all non-emergency high-alert parenteral doses for neonatal and paediatric patients where the ordered dose is not commercially available.
  • Provide all oral liquid high-alert medications in labelled pre-filled oral syringes.
  • Use standard concentrations of medications.

Communication and Documentation

  • Ensure all containers and syringes containing medication are labeled; adopt best practices for effective labeling.
  • Ensure handwritten and pre-printed orders identify whether laboratory monitoring is required before administration to measure the medication therapeutic level and effectiveness.
  • Implement a standardized organization-wide mechanism to distribute and track responses to internal and external medication alerts and recalls.

Equipment and Technology

  • Ensure adequate and appropriate supplies for preparing/measuring paediatric doses less than 1 mL (e.g., T.B. syringes).
  • Replace free flow IV systems with infusion pumps, especially for neonatal and paediatric patients. 
  • Ensure oral syringes are kept stocked in patient care areas for administration of oral liquid medications; do not use parenteral syringes to administer orally.

Computerized Prescriber Order Entry

  • Determine the type(s) of backup systems required to maintain adequate and safe patient ordering. 
  • Ensure order sets include lab tests and monitoring required whenever possible.
  • Work with vendors when creating parameters for customizing alerts, dosing, etc. and prohibit the cut and paste function from all e-record and Prescriber Order Entry (POE) systems.


  • Offer interdisciplinary-based educational sessions and in-situ simulation training related to safe medication practices, including (but not limited to):
    • Use and programming of smart pumps;
    • Computerized prescriber order entry system(s).

Post Incident Management

  • Retain medication syringes, bags, containers, vials, pumps and documentation involved in medication-related events.

Monitoring and Measuring 

  • Implement formal strategies to monitor and measure the effectiveness and efficiency of, and adherence to medication guidelines, protocols and algorithms, including:
    • Adoption of formal quality measures and indicators;
    • Order entry systems and automated dispensing machine overrides (i.e., assess frequency, type and appropriateness of overrides);
    • Sharing learnings from medication related no harm and harm incidents with teams and leadership (e.g., chart audits/trigger tools, incident reports, team debriefs, critical incident and quality of care committee reviews, medical legal claims, coroner reports and recommendations).


  • HIROC claims files.
  • Agency for Healthcare Research and Quality and Patient Safety Network. (2019). Medication errors and adverse drug events.
  • Canadian Medical Protective Association (CMPA). (2011). Risk management in elderly patients: Medication issues. Duties and responsibilities.
  • Canadian Patient Safety Institute and Health Quality Ontario. (2015). Never events for hospital care in Canada: Safer care for patients. 
  • ECRI Institute. (2008). Medication safety. Continuing care risk management: Self-assessment questionnaire 10.
  • Hill V, McMahon L, Stucke S, et al. (2017). Wide variation and excessive dosage of opioid prescriptions for common general surgical procedures. Ann Surg.  265(4):709–714.
  • Institute for Healthcare Improvement. (n.d.). High-alert medication safety. Topics. 
  • Institute for Safe Medication Practices Canada. (2000-2020). Definitions of terms.
  • Institute for Safe Medication Practices Canada. (2002). Inadvertent administration of oral solutions by injection. ISMP Canada Safety Bulletin. 2(1).
  • Institute for Safe Medication Practices Canada. (2003). Infusion pumps: Opportunities for improvement. ISMP Canada Safety Bulletin. 3(7)
  • Institute for Safe Medication Practices Canada. (2005). Lowering the risk of medication errors: independent double checks. ISMP Canada Safety Bulletin. 5(1).
  • Institute for Safe Medication Practices Canada. (2006). Eliminate use of dangerous. 
  • Institute for Safe Medication Practices Canada. (2006). Shared learning: Reported incidents involving hydromorphone. ISMP Canada Safety Bulletin. 9(6).
  • Institute for Safe Medication Practices Canada. (2007). Automated dispensing cabinets in the Canadian environment. ISMP Canada Safety Bulletin. 7(3).
  • Institute for Safe Medication Practices Canada. (2014). Advancing opioid safety for children in hospitals. ISMP Canadian Safety Bulletin. 14(3) 
  • Institute for Safe Medication Practices Canada. (2016). Accidental intravenous infusion of a heparinized irrigation in the operating room. ISMP Canada Safety Bulletin. 16(6).
  • Institute for Safe Medication Practices Canada. (2018). Dangerous abbreviations, symbols and dose designations. ISMP Canada Safety Bulletin. 6(4).
  • Institute for Safe Medication Practices Canada. (2018). ISMP list of high-alert medications in acute care settings.
  • Institute for Safe Medication Practices Canada. (2018). Reaffirming the “Do not use: Dangerous abbreviations, symbols and dose designations” list. ISMP Canada Safety Bulletin. 18(4).
  • Kaushal R, Bates W, Landrigan C, et al. (2001). Medication errors and adverse drug events in pediatric inpatients. JAMA. 285(16):2114-2120.
  • Manor P. (2010). CPOE: Strategies for success. Nursing Management, 41(5):18-20.
  • Morimoto T, Gandhi T, Seger A, et al. (2004). Adverse drug events and medication errors: Detection and classification methods. Qual Saf Health Care. 13(4):306-314.
  • Osterberg L, Blaschke T. (2005). Adherence to medication. N Engl J Med. 353(5):487-497.
  • Rozich J, Haraden C, Resar R. (2003). Adverse drug event trigger tool: A practical methodology for measuring medication related harm. Qual Saf Health Care. 12(3):194-200.
  • Smetzer J, Baker C, Byrne D, et al. (2010). Shaping systems for better behavioral choices: Lessons learned from a fatal medication error. Jt Comm J Qual Patient Saf. 36(4):152-163.
  • Staples P, Atkinson M, Wilson M, et al. (2008). Challenges of medical reconciliation in ambulatory care. The HIROC Connection. 19:5-6.
  • Tessier L, Guilcher T, Bai Q, et al. (2019). The impact of hospital harm on length of stay, costs of care and length of person-centred episodes of care: a retrospective cohort study. CMAJ. 191(32):E879-E885.