Medical Abbreviations: Common Terms, Meanings, and Safety Notes

Medical abbreviations are shortcuts used in clinical notes, medication records, laboratory reports, referrals, and everyday care communication. This searchable reference covers 100+ common terms used in charting, medications, labs, nursing, rehabilitation, and administration.

Use it as a reference, not a substitute for the patient record, an approved organizational abbreviation list, or clinical judgment.

Safety rule: If an abbreviation could reasonably have more than one meaning, verify it in context or write the term out in full.

Quick answer: common medical abbreviations

Common examples include BP (blood pressure), HR (heart rate), Hx (history), Dx (diagnosis), CBC (complete blood count), CT (computed tomography), IV (intravenous), and PRN (as needed). Context matters: PT may mean patient, physical therapy, physical therapist, or prothrombin time.

What are medical abbreviations?

Medical professionals use abbreviated language to document care efficiently. A term may be an abbreviation, an initialism, an acronym, or a symbol.

Abbreviation: a shortened word or phrase, such as Hx for history
Initialism: letters spoken individually, such as CBC for complete blood count
Acronym: initials spoken as a word, such as SOAP for subjective, objective, assessment, plan
Symbol: a mark such as > or <, which can be especially risky in documentation

Many terms are organization-specific. A useful abbreviation in one specialty, hospital, or electronic health record may be unclear elsewhere. For foundational vocabulary, see medical terminology.

Why medical abbreviations can create safety risks

Abbreviations can save time, but a misread shorthand can affect medication administration, diagnosis, orders, referrals, billing, or care transitions. The risk rises when handwriting is unclear, terminology crosses specialties, information is copied forward, or a patient reads wording without clinical context.

The Institute for Safe Medication Practices, The Joint Commission, and AHRQ PSNet have all highlighted error-prone abbreviation practices.

Abbreviation	Possible meanings	Why it needs context
BM	Bowel movement; bone marrow	Meaning depends on clinical setting.
D/C	Discontinue; discharge	Can change an order’s meaning.
ED	Emergency department; erectile dysfunction	Both occur in medical documentation.
LOC	Level of consciousness; loss of consciousness	Opposite implications are possible.
PA	Physician assistant; prior authorization	Administrative and clinical meanings overlap.
PE	Physical examination; pulmonary embolism	One is routine; one can be urgent.
POC	Point of care; plan of care	Common across several disciplines.
PT	Patient; physical therapy; physical therapist; prothrombin time	Always confirm the intended meaning.
RA	Room air; rheumatoid arthritis	Respiratory and rheumatology contexts differ.
UA	Urinalysis; unstable angina	Use the surrounding note and specialty.

Medical abbreviations list A–Z

A–D
E–H
I–M
N–R
S–W

A–D

Abbreviation	Meaning	Common context or safety note
A&O	Alert and oriented	Nursing or neurological assessment; document orientation domains when relevant.
ABG	Arterial blood gas	Respiratory status and critical-care laboratory testing.
abd	Abdomen or abdominal	Can also mean abduction in rehabilitation notes.
AC	Before meals	Use the full phrase in patient-facing instructions.
ACL	Anterior cruciate ligament	Orthopedics and sports medicine; document side and injury details.
ACS	Acute coronary syndrome	Spell out on first use in broad-audience documentation.
ADL	Activities of daily living	Common in nursing, occupational therapy, and rehabilitation.
AF / AFib	Atrial fibrillation	AF can also mean amniotic fluid.
AMA	Against medical advice	Can also refer to the American Medical Association.
aPTT	Activated partial thromboplastin time	Coagulation testing.
BID	Twice daily	Medication frequency; write out when policy requires.
BM	Bowel movement; bone marrow	Ambiguous without context.
BMI	Body mass index	Screening measure based on height and weight.
BP	Blood pressure	Use units and measurement conditions where appropriate.
BMP	Basic metabolic panel	Common electrolyte and renal-function test panel.
BUN	Blood urea nitrogen	Laboratory marker often considered with creatinine and hydration status.
CAD	Coronary artery disease	Cardiovascular history or diagnosis.
CBC	Complete blood count	Blood-cell test panel.
CHF	Congestive heart failure	Some organizations prefer heart failure with type and acuity specified.
C/O	Complains of	May be less clear than writing reports or presents with.
c/w	Consistent with	Can be misread; consider spelling out.
COPD	Chronic obstructive pulmonary disease	Respiratory diagnosis.
CMP	Comprehensive metabolic panel	Laboratory test panel.
CT	Computed tomography	Can also mean chest tube in some contexts.
CXR	Chest X-ray	Diagnostic imaging.
D/C	Discontinue; discharge	Avoid in orders. Write the intended term in full.
DNI	Do not intubate	Verify against current goals-of-care documentation.
DNR	Do not resuscitate	Verify against current code-status documentation.
DKA	Diabetic ketoacidosis	Acute metabolic complication of diabetes.
DM	Diabetes mellitus	Specify type when clinically relevant.
DOB	Date of birth	Protected health information; handle appropriately.
DOE	Dyspnea on exertion	Document severity, triggers, and associated symptoms.
DVT	Deep vein thrombosis	Potentially urgent vascular diagnosis.
Dx	Diagnosis	Often paired with assessment or problem-list documentation.

E–H

Abbreviation	Meaning	Common context or safety note
ECG / EKG	Electrocardiogram	Both forms are widely used.
ED	Emergency department; erectile dysfunction	Use context or spell out.
EHR / EMR	Electronic health record / electronic medical record	Often used interchangeably, though organizations may distinguish them.
eGFR	Estimated glomerular filtration rate	Kidney-function estimate.
ENT	Ear, nose, and throat	Specialty or anatomical region.
ESR	Erythrocyte sedimentation rate	Nonspecific inflammation marker.
ESRD	End-stage renal disease	Some settings use updated kidney-disease terminology.
F/U	Follow-up	May be clearer when written in full.
Fx	Fracture	Document body part, side, and type.
GCS	Glasgow Coma Scale	Document component scores when appropriate.
GI	Gastrointestinal	Digestive system or gastroenterology context.
H&P	History and physical	Initial clinical assessment documentation.
Hb / Hgb	Hemoglobin	Laboratory measurement.
HDL	High-density lipoprotein	Lipid-panel component.
HIV	Human immunodeficiency virus	Use privacy-conscious language and follow confidentiality policy.
HPI	History of present illness	Clinical history section.
HR	Heart rate	Document rhythm or measurement context when relevant.
Hx	History	Examples include PMH, family history, and social history.

I–M

Abbreviation	Meaning	Common context or safety note
ICU	Intensive care unit	Critical-care setting.
IM	Intramuscular	Medication route.
I&O	Intake and output	Nursing fluid-balance documentation.
INR	International normalized ratio	Coagulation test, often relevant to anticoagulation management.
IV	Intravenous	Medication, fluid, or access route.
LDL	Low-density lipoprotein	Lipid-panel component.
LMP	Last menstrual period	Reproductive-health history.
LOC	Level of consciousness; loss of consciousness	Write out if ambiguity is possible.
MI	Myocardial infarction	Heart attack.
MRI	Magnetic resonance imaging	Diagnostic imaging.

N–R

Abbreviation	Meaning	Common context or safety note
N/V	Nausea and vomiting	Document duration, severity, and related symptoms when needed.
NKA	No known allergies	Confirm what was assessed.
NKDA	No known drug allergies	Does not necessarily mean no non-drug allergies.
NPO	Nothing by mouth	Use the full instruction for patient-facing communication.
NSAID	Nonsteroidal anti-inflammatory drug	Medication class.
O2	Oxygen	Document delivery method and flow or concentration as appropriate.
OOB	Out of bed	Nursing and mobility documentation.
OTC	Over the counter	Non-prescription medication context.
PA	Physician assistant; prior authorization	Ambiguous between clinical and administrative use.
PCP	Primary care provider	May also be expanded differently by local policy.
PERRLA	Pupils equal, round, reactive to light and accommodation	Neurological or eye assessment.
PE	Physical examination; pulmonary embolism	Use context or write out.
PICC	Peripherally inserted central catheter	Vascular-access device.
PMH	Past medical history	Patient history section.
POC	Point of care; plan of care	Ambiguous across specialties.
PO	By mouth	Medication route.
PRN	As needed	Medication orders should also state indication, interval, and limits.
PT	Patient; physical therapy; physical therapist; prothrombin time	One of the most context-dependent abbreviations.
q	Every	Medication frequency shorthand; use carefully.
qHS	Every night at bedtime	Medication frequency shorthand.
QID	Four times daily	Medication frequency shorthand.
RA	Room air; rheumatoid arthritis	Ambiguous across clinical contexts.
RBC	Red blood cell	Laboratory measurement or component.
ROM	Range of motion	Rehabilitation and musculoskeletal assessment.
ROS	Review of systems	Clinical history section.
RR	Respiratory rate	Vital sign.
R/O	Rule out	Can be misunderstood as a confirmed diagnosis; clarify status.
Rx	Prescription or treatment	Meaning depends on context.

S–W

Abbreviation	Meaning	Common context or safety note
S/P	Status post	Write out when clarity matters.
SOB	Shortness of breath	Document severity, onset, triggers, and oxygen status as relevant.
SOAP	Subjective, objective, assessment, plan	Common note structure.
SpO2	Peripheral oxygen saturation	Document device, oxygen support, and measurement context.
STAT	Immediately	Reserve for genuinely urgent actions under local policy.
TID	Three times daily	Medication frequency shorthand.
Tx	Treatment	May be clearer when written in full.
UA	Urinalysis; unstable angina	Use context or spell out.
UTI	Urinary tract infection	Clinical diagnosis.
VS	Vital signs	Usually includes temperature, pulse, respiratory rate, blood pressure, and oxygenation as applicable.
WBC	White blood cell	Laboratory measurement or component.
WFL	Within functional limits	Common in rehabilitation documentation.
WNL	Within normal limits	Use only when the applicable normal standard is clear.

Medical charting abbreviations

Charting shorthand often appears in progress notes, assessments, handoffs, and structured documentation. Common examples include A&O, H&P, HPI, PMH, ROS, SOAP, VS, and WNL.

Safe charting is specific. Rather than relying on a broad term such as WNL, document the actual finding when it affects clinical decisions, continuity of care, or billing.

Medication abbreviations and prescription shorthand

Abbreviation	Meaning	Safer documentation reminder
AC	Before meals	Use full words for patient instructions when possible.
BID	Twice daily	Follow local policy for frequency terminology.
IM	Intramuscular	State route clearly.
IV	Intravenous	State route clearly.
NPO	Nothing by mouth	Clarify exact restrictions and duration.
PO	By mouth	State route clearly.
PRN	As needed	Include reason, interval, maximum dose, and monitoring requirements.
qHS	Every night at bedtime	Confirm organization-approved wording.
QID	Four times daily	Confirm organization-approved wording.
TID	Three times daily	Confirm organization-approved wording.

A complete medication order generally needs the medication name, strength, dose, route, frequency, indication where appropriate, and relevant maximums or monitoring instructions. Never assume missing information from an abbreviation alone.

Lab and diagnostic abbreviations

Abbreviation	Meaning	What it generally refers to
ABG	Arterial blood gas	Oxygenation, ventilation, and acid-base status.
aPTT	Activated partial thromboplastin time	Coagulation testing.
BMP	Basic metabolic panel	Electrolytes and renal-related values.
BUN	Blood urea nitrogen	Renal function and hydration context.
CBC	Complete blood count	Blood-cell measurements.
CMP	Comprehensive metabolic panel	Broader metabolic and organ-function testing.
CT	Computed tomography	Cross-sectional diagnostic imaging.
ECG / EKG	Electrocardiogram	Electrical activity of the heart.
eGFR	Estimated glomerular filtration rate	Kidney-function estimate.
Hb / Hgb	Hemoglobin	Oxygen-carrying protein measurement.
INR	International normalized ratio	Clotting tendency.
MRI	Magnetic resonance imaging	Diagnostic imaging using magnetic fields and radio waves.
UA	Urinalysis	Urine testing; confirm context because UA can mean something else.
WBC	White blood cell	Laboratory cell count or component.

Test names alone do not explain a result. Interpretation depends on reference ranges, symptoms, medications, timing, collection method, and the care team’s assessment.

Common nursing abbreviations

Abbreviation	Meaning
A&O	Alert and oriented
ADL	Activities of daily living
BP	Blood pressure
HR	Heart rate
I&O	Intake and output
NKA / NKDA	No known allergies / no known drug allergies
O2	Oxygen
OOB	Out of bed
RR	Respiratory rate
SpO2	Peripheral oxygen saturation
VS	Vital signs

Each organization may maintain an approved abbreviation list. For more specialty-specific examples, see nursing abbreviations.

Physical therapy and rehabilitation abbreviations

Abbreviation	Meaning	Typical use
AAROM	Active-assisted range of motion	Movement completed with patient effort and assistance.
ADL	Activities of daily living	Functional-status assessment.
HEP	Home exercise program	Exercises assigned outside treatment sessions.
POC	Plan of care	Rehabilitation treatment plan; may also mean point of care elsewhere.
PROM	Passive range of motion	Movement performed without active patient muscle effort.
ROM	Range of motion	Joint movement measurement.
WB	Weight bearing	Document the precise restriction or status.
WFL	Within functional limits	Functional assessment shorthand.
WNL	Within normal limits	Use only where a normal standard is defined and relevant.

For high-quality rehabilitation documentation, add the body region, side, measured finding, intervention, patient response, and plan. Tools that support structured workflows can help clinicians document more consistently, including Jane App documentation, WebPT documentation, and AI-assisted physical therapy documentation. The clinician remains responsible for reviewing and finalizing every note.

Administrative and health-record abbreviations

Abbreviation	Meaning	Note
AMA	Against medical advice	Can also mean American Medical Association.
DOB	Date of birth	Protected health information.
EHR	Electronic health record	Digital longitudinal health record.
EMR	Electronic medical record	Often used interchangeably with EHR.
F/U	Follow-up	May be clearer when spelled out.
PA	Prior authorization; physician assistant	Use context or write out.
PCP	Primary care provider	Care coordination and referral context.

Abbreviations do not reduce privacy obligations. Use minimum-necessary information, avoid unnecessary identifiers, and follow your organization’s policy on patient confidentiality.

Medical abbreviations to verify or avoid

Some shorthand is widely discouraged because it can be misread. Follow your local policy, since approved terminology varies by organization and jurisdiction.

Risky term	Safer alternative	Why
U or u	Write units	May be mistaken for a zero or another character.
IU	Write international units or approved full wording	Can be misread as IV or 10.
QD or QOD	Write daily or every other day	Easy to confuse.
Trailing zero, such as 1.0 mg	Write 1 mg	May be read as 10 mg.
No leading zero, such as .5 mg	Write 0.5 mg	May be read as 5 mg.
MS, MSO4, MgSO4	Write the full medication name	Can be confused with another drug.
cc	Write mL	Can be mistaken for other characters.
µg or mcg symbols	Use locally approved full wording	Symbols can be misread.
AD, AS, AU	Write right ear, left ear, or both ears	Route abbreviations can be confused.
OD, OS, OU	Write right eye, left eye, or both eyes	Route abbreviations can be confused.
SC, SQ, sq, sub q	Write subcutaneous or approved wording	Formats vary and can be misread.
< or >	Write less than or greater than	Symbols can be reversed or unclear.
Arrows	Write increase or decrease	Arrows may be misunderstood or lost in copying.
Drug-name shortcuts	Write the complete approved medication name	Look-alike and sound-alike medication risk.
D/C	Write discontinue or discharge	Two very different meanings.
PT, PE, ED, RA, PA, LOC	Spell out when ambiguity is possible	Meaning depends heavily on specialty and context.

Important: Commonly used does not always mean approved. Check your organization’s current abbreviation policy before using shorthand in an order, medication record, discharge instruction, or patient-facing document.

How to document medical abbreviations clearly and safely

Follow one approved abbreviation list. Do not invent local shorthand.
Spell out a term on first use. Add the abbreviation in parentheses only if it will appear again.
Write medication instructions completely. Include dose, route, frequency, indication, and limits.
Use structured fields when available. They reduce ambiguity in vital signs, medications, allergies, and orders.
Make uncertainty explicit. Do not let rule out look like a confirmed diagnosis.
Expand shortcuts in patient instructions. Plain language supports safer follow-through.
Protect confidentiality. Avoid unnecessary identifiers in messages, screenshots, and shared notes.
Ask when unclear. Clarification is safer than guessing, especially for medications, critical values, and care transitions.

Medical abbreviations FAQ

What are the most common medical abbreviations?

Common examples include BP for blood pressure, HR for heart rate, Hx for history, Dx for diagnosis, CBC for complete blood count, IV for intravenous, and PRN for as needed.

What are common charting abbreviations?

Frequently used charting terms include H&P, HPI, PMH, ROS, SOAP, A&O, VS, and WNL. Their use should follow organizational policy and documentation standards.

What is the difference between an abbreviation and an acronym?

An abbreviation shortens a word or phrase. An acronym is generally formed from initials and spoken as a word. In everyday clinical use, the terms are often used loosely.

Is there one official medical abbreviations list?

No. National safety organizations publish guidance on error-prone abbreviations, but hospitals, practices, specialties, and EHR systems can have their own approved lists and restrictions.

How do I look up an unfamiliar abbreviation?

Start with the source document and clinical context. Then check your organization’s approved resources, ask the author or responsible clinician, and avoid acting on unclear medication or order terminology until it is clarified.

What does medical abbreviations list mean?

It usually refers to a reference that pairs medical shorthand with its full meaning. A safe list also identifies ambiguous or discouraged abbreviations rather than presenting every term as universally acceptable.

Which medical abbreviations should not be used?

Commonly discouraged terms include U, IU, QD, QOD, ambiguous dose formatting, some route abbreviations, D/C, and shorthand medication names. Use your local policy as the final authority.

Can patients ask what an abbreviation means?

Yes. Patients can ask the care team to explain wording in a note, test result, medication instruction, or after-visit summary. Do not rely on a glossary alone to interpret a diagnosis or treatment decision.

Can AI-generated notes use medical abbreviations?

AI-assisted documentation should follow the same approved terminology and privacy standards as any other note. A qualified clinician must review, correct, and finalize the record.

Should patient instructions include abbreviations?

Whenever possible, patient instructions should use plain language. If an abbreviation is necessary, explain it clearly where it appears.

Sources and further reading

Last reviewed: August 2026. This reference is educational and should be used alongside current institutional policy and clinical guidance.