Annual Probability of a Prescription Medication Error

Medication errors affect an estimated 1.5 million Americans each year and cause at least one death per day, according to the Institute of Medicine. Pharmacy dispensing errors occur in approximately 1-4% of all prescriptions filled (about 2% on average), meaning that out of approximately 6.3 billion prescriptions dispensed annually, over 100 million may contain some type of error.

The most common types of medication errors include wrong drug dispensed, wrong dose, wrong patient, drug interactions not caught, wrong route of administration, and omission of a needed medication. Look-alike and sound-alike drug names are a frequent contributor to errors. Hospital medication errors are even more common, affecting about 5-10% of hospitalized patients.

Medication errors cause approximately 7,000-9,000 deaths per year and contribute to an estimated $40 billion in additional healthcare costs. Prevention strategies include electronic prescribing (which reduces handwriting misinterpretation), barcode verification systems, pharmacist double-checking, patient medication reviews, and patient engagement (knowing your medications, asking questions, and checking labels). Patients should always verify their medication name, dose, and instructions when picking up a prescription.