Key Takeaways

  • High-alert medications have increased risk of causing significant patient harm when used in error.
  • ISMP maintains a list of high-alert medications that require extra safeguards in pharmacy practice.
  • Look-alike/sound-alike (LASA) medications can be confused due to similar names or packaging.
  • Tall Man lettering (e.g., hydrOXYzine vs. hydrALAzine) helps distinguish LASA drug names.
  • Physical separation of LASA drugs on shelves and use of alert labels are key prevention strategies.
Last updated: January 2026

High-Alert and Look-Alike/Sound-Alike Medications

Quick Answer: High-alert medications can cause severe harm if given incorrectly. LASA drugs have similar names or appearance and are easily confused. Prevention strategies include Tall Man lettering, physical separation on shelves, independent double-checks, and auxiliary warning labels.

High-Alert Medications

High-alert medications are drugs that bear a heightened risk of causing significant patient harm when used in error. While mistakes may not be more frequent with these drugs, the consequences of an error are much more serious.

Common High-Alert Medication Classes

CategoryExamplesRisk
AnticoagulantsWarfarin, heparin, enoxaparinBleeding complications
InsulinsRegular, NPH, glargine, lisproHypoglycemia
OpioidsMorphine, fentanyl, hydromorphoneRespiratory depression
ChemotherapyMethotrexate, vincristineOrgan toxicity
Concentrated ElectrolytesPotassium chloride (IV), sodium chloride 23.4%Cardiac arrest
Neuromuscular Blocking AgentsSuccinylcholine, vecuroniumRespiratory paralysis
Oral HypoglycemicsMetformin, glipizide, glyburideSevere hypoglycemia
IV Contrast AgentsIodinated contrastAllergic reactions, renal injury

Safeguards for High-Alert Medications

SafeguardDescription
Independent Double-CheckSecond person verifies calculation and drug
Dose LimitsSystem alerts for unusual doses
Standardized ConcentrationsUse consistent preparations
Restricted AccessStore in secure locations
Auxiliary LabelsWarning stickers on containers
Patient EducationCounsel on risks and monitoring

Look-Alike/Sound-Alike (LASA) Medications

LASA medications are drug pairs that look or sound similar and can be confused with each other.

Common LASA Drug Pairs

Drug 1Drug 2Tall Man Lettering
HydroxyzineHydralazinehydrOXYzine / hydrALAzine
MetforminMetronidazolemetFORMIN / metroNIDAZOLE
ClonidineClonazepamcloNIDine / clonaZEPAM
PrednisolonePrednisoneprednisoLONE / predniSONE
DopamineDobutamineDOPamine / DOBUTamine
CelebrexCelexaCeleBREX / CeleXA
HumalogHumulinHumaLOG / HumuLIN
TramadolTrazodonetraMADol / traZODone
NovolinNovologNovoLIN / NovoLOG
BupropionBuspironebuPROPion / busPIRone
VincristineVinblastinevinCRIStine / vinBLAStine
LamictalLamisilLamiCTAL / LamiSIL

Preventing LASA Errors

  1. Tall Man Lettering - Capitalize distinguishing letters (e.g., hydrOXYzine)
  2. Physical Separation - Store LASA drugs in different locations
  3. Alert Labels - Use warning stickers on shelves and bottles
  4. Both Brand and Generic Names - Use both names when possible
  5. Read Back Orders - Verbally confirm medication names
  6. Barcode Scanning - Verify correct drug at point of dispensing

ISMP and Joint Commission Resources

OrganizationRole
ISMP (Institute for Safe Medication Practices)Publishes high-alert medication lists; LASA list
The Joint CommissionRequires LASA management strategies for accreditation
FDAReviews drug names before approval to minimize confusion

Exam Tip: Know common LASA drug pairs and how Tall Man lettering is used. Also memorize high-alert medication categories.

Test Your Knowledge

Which of the following medications would be classified as a high-alert medication?

A
B
C
D
Test Your Knowledge

The use of "hydrOXYzine" and "hydrALAzine" with capital letters is an example of which safety strategy?

A
B
C
D
Test Your Knowledge

Which organization publishes the widely-used list of high-alert medications and LASA drug pairs?

A
B
C
D