| Abbreviation | Intended Meaning | Why It's Dangerous | Write Instead |
|---|---|---|---|
| U or u | Units | Mistaken for "0" (zero), "4", or "cc" — causing 10x overdoses of insulin and heparin | "units" (spelled out) |
| IU | International Units | Mistaken for "IV" (intravenous) or "10" | "international units" (spelled out) |
| QD or q.d. | Every day | Mistaken for "QID" (four times a day) when poorly written | "daily" |
| QOD or q.o.d. | Every other day | Mistaken for "QD" (every day) or "QID" (four times daily) | "every other day" |
| Trailing zero (1.0 mg) | 1 mg | Decimal point missed → read as 10 mg (10x overdose) | "1 mg" (never write trailing zero) |
| Naked decimal (.5 mg) | 0.5 mg | Decimal point missed → read as 5 mg (10x overdose) | "0.5 mg" (always write leading zero) |
| MS, MSO4, MgSO4 | Morphine sulfate OR magnesium sulfate | MS confuses morphine with magnesium — opposite clinical contexts | "morphine sulfate" or "magnesium sulfate" (spelled out) |
| Abbreviation | Meaning | Normal Range (Adult) |
|---|---|---|
| VS | Vital signs | — |
| BP | Blood pressure | 90–120/60–80 mmHg |
| SBP / DBP | Systolic / diastolic blood pressure | SBP <120, DBP <80 (normal) |
| MAP | Mean arterial pressure | 70–100 mmHg (goal ≥65 in sepsis) |
| HR | Heart rate | 60–100 bpm |
| RR | Respiratory rate | 12–20 breaths/min |
| Temp or T | Temperature | 97.8–99.1°F (36.5–37.3°C) oral |
| SpO2 | Oxygen saturation (pulse oximetry) | ≥95% |
| SaO2 | Arterial oxygen saturation (ABG) | 95–100% |
| GCS | Glasgow Coma Scale | 15 (normal); <8 = severe impairment |
| UO or UOP | Urine output | ≥0.5 mL/kg/hr |
| I&O | Intake and output | — |
| CVP | Central venous pressure | 2–8 mmHg |
| ICP | Intracranial pressure | <20 mmHg |
| CPP | Cerebral perfusion pressure | 60–70 mmHg (CPP = MAP − ICP) |
| Abbreviation | Meaning | Notes |
|---|---|---|
| QD or daily | Once daily | QD is on the Do Not Use list — use "daily" |
| BID | Twice daily | Approximately every 12 hours |
| TID | Three times daily | Approximately every 8 hours |
| QID | Four times daily | Approximately every 6 hours |
| Q4H or q4h | Every 4 hours | 6 doses per 24 hours |
| Q6H | Every 6 hours | 4 doses per 24 hours |
| Q8H | Every 8 hours | 3 doses per 24 hours |
| Q12H | Every 12 hours | 2 doses per 24 hours |
| PRN | As needed (pro re nata) | Must specify frequency and indication |
| STAT | Immediately | From Latin "statim"; give within minutes |
| AC | Before meals (ante cibum) | Common for insulin orders |
| PC | After meals (post cibum) | — |
| HS or QHS | At bedtime (hora somni) | — |
| NPO | Nothing by mouth (nil per os) | No food, fluid, or oral medications (unless specified) |
| Abbreviation | Route |
|---|---|
| PO or po | By mouth (per os) |
| SL | Sublingual (under the tongue) |
| SQ or SubQ | Subcutaneous |
| IM | Intramuscular |
| IV | Intravenous |
| IVPB | Intravenous piggyback (secondary infusion) |
| IVP | IV push (bolus injection) |
| GT or G-tube | Gastrostomy tube |
| NGT | Nasogastric tube |
| PR | Per rectum (rectal) |
| TOP or Topical | Applied to the skin surface |
| INH | Inhaled |
| ID | Intradermal (tuberculin test placement) |
| Abbreviation | Full Name | Clinical Significance |
|---|---|---|
| CBC | Complete blood count | WBC, RBC, Hgb, Hct, platelets |
| WBC | White blood cell count | Normal 4.5–11.0 × 10³/µL |
| Hgb / Hb | Hemoglobin | Normal 12–17 g/dL (F/M) |
| Hct | Hematocrit | ~3× hemoglobin value |
| Plt | Platelets | Normal 150,000–400,000/µL |
| BMP | Basic metabolic panel | Na, K, Cl, CO2, BUN, Cr, glucose, calcium |
| CMP | Comprehensive metabolic panel | BMP + liver function tests (LFTs), total protein, albumin |
| BUN | Blood urea nitrogen | Normal 7–20 mg/dL; elevated in renal failure or dehydration |
| Cr or SCr | Creatinine (serum) | Normal ~0.6–1.2 mg/dL |
| K or K+ | Potassium | Normal 3.5–5.0 mEq/L; critical <3.0 or >6.0 |
| Na or Na+ | Sodium | Normal 135–145 mEq/L |
| Mg | Magnesium | Normal 1.7–2.2 mg/dL |
| Ca or Ca2+ | Calcium | Normal 8.5–10.5 mg/dL (ionized 1.1–1.4 mmol/L) |
| Phos | Phosphate | Normal 2.5–4.5 mg/dL |
| Lac | Lactate | Normal <2 mmol/L; >4 = severe shock/hypoperfusion |
| ABG | Arterial blood gas | pH, PaO2, PaCO2, HCO3, base excess |
| INR | International normalized ratio | Normal 0.8–1.2; therapeutic anticoagulation 2–3 |
| PTT / aPTT | Partial thromboplastin time | Monitors heparin therapy; normal 25–35 sec |
| PT | Prothrombin time | Normal 11–13 sec |
| Trop or cTnI | Troponin (cardiac) | Elevated in myocardial injury |
| BNP / NT-proBNP | B-type natriuretic peptide | Elevated in heart failure |
| LFTs | Liver function tests | AST, ALT, ALP, bilirubin, albumin |
| UA | Urinalysis | Dipstick + microscopy |
| C&S or C/S | Culture and sensitivity | Identifies organism and antibiotic susceptibility |
| ABX | Antibiotics | Common shorthand in clinical notes |
| CXR | Chest X-ray | — |
| CT or CAT scan | Computed tomography | — |
| MRI | Magnetic resonance imaging | — |
| ECG or EKG | Electrocardiogram | 12-lead cardiac tracing |
| ECHO | Echocardiogram | Cardiac ultrasound |
| Abbreviation | Full Term |
|---|---|
| ACS | Acute coronary syndrome (STEMI, NSTEMI, unstable angina) |
| AKI | Acute kidney injury |
| ARDS | Acute respiratory distress syndrome |
| CAD | Coronary artery disease |
| CHF | Congestive heart failure |
| COPD | Chronic obstructive pulmonary disease |
| CVA | Cerebrovascular accident (stroke) |
| DKA | Diabetic ketoacidosis |
| DVT | Deep vein thrombosis |
| HAP / VAP | Hospital-acquired / ventilator-associated pneumonia |
| HF | Heart failure |
| HTN | Hypertension |
| MI | Myocardial infarction |
| PE | Pulmonary embolism |
| PNA | Pneumonia |
| SIRS | Systemic inflammatory response syndrome |
| SOB or DOE | Shortness of breath / dyspnea on exertion |
| TIA | Transient ischemic attack |
| UTI | Urinary tract infection |
| Abbreviation | Meaning |
|---|---|
| A&O or A&Ox4 | Alert and oriented (x4 = person, place, time, situation) |
| AAOx3 | Awake, alert, and oriented to person, place, time |
| WNL | Within normal limits |
| NAD | No acute distress |
| c/o | Complains of |
| s/s or S&S | Signs and symptoms |
| Hx | History |
| CC | Chief complaint |
| PMH | Past medical history |
| FH | Family history |
| SH | Social history |
| ROS | Review of systems |
| Dx | Diagnosis |
| Tx | Treatment |
| Rx | Prescription / medication |
| Sx | Symptoms |
| Pt | Patient |
| MD / PA / NP | Medical doctor / physician assistant / nurse practitioner |
| HCP | Healthcare provider |
| DC or d/c | Discharge (or discontinue — context matters; verify) |
| w/u | Workup |
| f/u | Follow-up |
| prn | As needed |
| NKDA | No known drug allergies |
| NKA | No known allergies |
| DNR / DNI | Do not resuscitate / do not intubate |
| FULL CODE | All resuscitative measures authorized |
| POC | Plan of care (or point of care, depending on context) |
Related guides: Dosage calculations | Medication administration routes | Blood glucose | SBAR handoff
This article is general educational information for licensed clinicians and students, not medical advice or a substitute for your institution's protocols, pharmacy guidance, or a provider's orders. Always follow facility policy and verify doses independently.
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