Using Two Patient Identifiers in the Pharmacy for Safety: How to Prevent Medication Errors

Every year, thousands of patients in the U.S. get the wrong medication-not because the pharmacist made a mistake with the pill, but because they gave it to the wrong person. This isn’t rare. It’s systemic. And the fix? Simple, but often ignored: use two patient identifiers before handing out any prescription.

Why Two Identifiers? It’s Not Just a Rule-It’s a Lifesaver

The Joint Commission, the group that accredits U.S. hospitals and pharmacies, made this rule official back in 2003. NPSG.01.01.01 says: Never rely on just one thing to confirm who a patient is. That means no more just asking, “Are you John Smith?” and assuming the answer is yes. You need two pieces of information that are unique to that person-like their full name and date of birth. Or name and medical record number. Or name and phone number.

Room numbers? No. Diagnosis codes? No. Even “the guy in bed 3” isn’t enough. Those can change. Those can be wrong. And when they are, someone could get a drug they’re allergic to, a double dose, or a medication that clashes with something they’re already taking.

A 2020 study in JMIR Medical Informatics found that up to 10% of serious drug interaction alerts get missed because systems can’t link a patient’s full history. That’s about 6,000 people a year getting dangerous combinations because their records were split across systems-or worse, because a pharmacist didn’t check the right name.

What Counts as a Valid Identifier?

Not everything you think is unique actually is. Here’s what The Joint Commission says works:

• Full legal name (first and last)
• Date of birth
• Assigned medical record number
• Telephone number
• Other unique personal identifiers (like a national ID if used locally)

And here’s what doesn’t:

• Room number
• Location (e.g., “the woman in aisle 2”)
• Diagnosis
• Prescription number
• Insurance ID

Why? Because room numbers change. Insurance IDs can be shared across families. Diagnosis codes don’t identify the person-they describe the illness. You’re verifying the person, not the condition.

Manual Checks Alone Aren’t Enough

You might think, “I just ask the patient twice-name and DOB. That’s fine.” But human memory is messy. People forget their birth year. They give nicknames. They say “I’m John Smith” when they’re actually Jonathan Smith from the next town. And in a busy pharmacy, especially during lunch rush or flu season, staff get tired. They start skipping steps.

A 2023 survey by the American Society of Health-System Pharmacists (ASHP) found that 63% of pharmacists admitted to occasionally cutting corners on verification because of time pressure. In community pharmacies, 42% said verification often happens verbally-with no written record. That’s a problem. If there’s no documentation, there’s no accountability. And if there’s no accountability, mistakes slip through.

One real case from Imprivata in 2023 involved a patient transferred from another hospital. He was unconscious. The receiving hospital couldn’t find his record because he was registered under his middle name, not his first. They created a new file. Days later, they discovered he had a documented penicillin allergy-right in his old record. If the pharmacy had checked two identifiers properly, they’d have found it.

Technology Makes It Faster and Safer

The best way to fix this isn’t by yelling at staff to be more careful. It’s by making it impossible to skip the check.

Barcode scanning is the gold standard. When a pharmacist pulls a prescription, they scan the patient’s wristband (with name and MRN encoded) and the medication’s barcode. The system cross-checks: Is this the right drug? Is it for this patient? Is the dose correct? If anything’s off, it stops.

A 2012 study in the Journal of Patient Safety showed that hospitals using barcode systems saw a 75% drop in medication errors reaching patients. That’s not a small win. That’s life-or-death.

Even better? Biometric systems. Companies like Imprivata PatientSecure use palm-vein scanning. No one shares your vein pattern. No one can fake it. A 2024 Altera Health survey found these systems match patients to records 94% of the time. Compare that to hospitals without good systems-only 17% accuracy.

And here’s the kicker: biometric verification takes under 10 seconds. Faster than asking two questions. And it doesn’t rely on the patient being awake, coherent, or honest.

What About Double Checking by Two People?

You’ve probably heard: “Have two pharmacists check the prescription.” Sounds safe, right?

Turns out, it doesn’t work as well as you think.

A 2020 review in BMJ Quality & Safety looked at 18 studies on double-checking. Result? No solid proof it reduces errors. Why? Because if both people are looking at the same screen, reading the same name, and trusting the same system-they’re likely to miss the same mistake. Independent double-checking only works if the second person doesn’t just nod along. And most times, they don’t.

Technology doesn’t replace human judgment. But it removes the chance for human error to creep in at the verification stage.

Why Do Pharmacies Still Get It Wrong?

There are three big reasons:

1. Duplicate records: A patient visits five different clinics. Each one creates a new file. Now there are three “John Smiths” in the system. One has allergies. One has diabetes. One has a history of substance use. If the pharmacy pulls the wrong one, disaster follows.
2. Legacy systems: Many pharmacies still use old software that doesn’t talk to each other. No Enterprise Master Patient Index (EMPI) means no central record. No EMPI = 8-12% of patient records are duplicated or mismatched. That’s not a glitch. That’s the norm in underfunded systems.
3. Staff burnout: Community pharmacists are stretched thin. One study showed pharmacists spend 40% of their day on administrative tasks. When you’re rushing, skipping a step feels harmless. Until it’s not.

How to Implement This Right

If you’re in charge of a pharmacy, here’s how to do it without chaos:

1. Start with policy. Write down exactly which two identifiers you’ll use-and which ones are banned. Make it clear. Post it.
2. Train everyone. Not just pharmacists. Techs, cashiers, even the person who hands out pickup bags. Everyone touches the process.
3. Pilot it. Try it in one section for a month. Track near-misses. See where it breaks.
4. Go tech-heavy. If you can’t afford biometrics, start with barcode scanners. They’re affordable, proven, and easy to integrate.
5. Document everything. The Joint Commission found that 37% of non-compliant pharmacies didn’t even record the verification. That’s not safety. That’s negligence.

What Happens If You Don’t?

The Joint Commission doesn’t just say “please.” They enforce it. In 2023, non-compliance with two-identifier rules was the third most common violation in hospital surveys. That’s not a footnote. That’s a red flag.

Lose accreditation? You lose Medicare and Medicaid payments. That’s not just money. That’s survival.

And the cost of a single error? A patient dies. Or goes blind. Or loses a limb from a wrong drug. The financial cost? Up to $40 million a year per large hospital system just to fix duplicate records and clean up errors.

The Future Is Unique Identifiers

The Office of the National Coordinator for Health IT is running a pilot in early 2025 to test a national, voluntary patient identifier system. Think of it like a Social Security number for health records-unique, secure, and linked across all providers.

Right now, we’re stuck with patchwork systems. But the data is clear: without a single, reliable identifier, we’re just guessing who’s who. And guessing with medications? That’s not risk management. That’s gambling.

The American Medical Informatics Association says a national system could catch up to 9.7% more dangerous drug interactions. That’s thousands of people spared harm every year.

Bottom Line: This Isn’t Optional

Using two patient identifiers isn’t bureaucracy. It’s basic science. You wouldn’t give insulin to someone without checking their blood sugar. You wouldn’t give an antibiotic without knowing the infection. So why give a pill without knowing the person?

The tools are here. The data proves it works. The cost of doing nothing is too high.

If you’re a pharmacist: scan the wristband. Say the name. Confirm the birthdate. Write it down.

If you’re a patient: Don’t be shy. Ask, “Are you sure this is for me?”

Because in a pharmacy, the difference between safety and disaster isn’t a fancy algorithm. It’s two questions. And the courage to ask them.