Medical abbreviations

a.c. means “before meals”: the medicine is given before eating, usually about 30 minutes before. You see it with insulin, some diabetes drugs and drugs that are absorbed better on an empty stomach.

Latin: ante cibum

A&E is the UK name for the emergency department (ED).

A test on arterial blood measuring pH, PaO₂, PaCO₂, bicarbonate and often lactate and electrolytes.

An umbrella term for unstable angina, NSTEMI and STEMI.

Ad lib means “as much as wanted”: for example oral fluids or activity allowed freely, with no set limit.

Latin: ad libitum

Basic self-care tasks such as washing, dressing, eating, toileting and moving, used to assess independence.

An irregular, often fast heart rhythm that increases the risk of stroke. In the US it is often written “AFib”.

A sudden drop in kidney function over hours to days, detected by rising creatinine or falling urine output.

Resuscitation by trained teams, adding airway management, drugs and manual defibrillation to BLS. In neurology ALS also means amyotrophic lateral sclerosis.

A clotting test of the intrinsic and common pathways, used mainly to monitor unfractionated heparin infusions.

Severe, acute lung inflammation causing low oxygen levels, graded partly by the PaO₂/FiO₂ ratio.

A quick four-level check of consciousness: is the patient alert, responding to voice, responding only to pain, or unresponsive?

b.d. means twice a day. It is the UK and Australian form of b.i.d.

Latin: bis die

b.i.d. means twice a day: two doses in 24 hours, usually morning and evening. It is mostly a US abbreviation; UK charts write “b.d.”.

Latin: bis in die

The first steps of resuscitation: recognising arrest, calling for help, chest compressions, ventilation and defibrillation with an AED.

In UK wards “BM” is slang for a finger-prick blood glucose, from the old BM-Test strips. In US and other notes BM usually means a bowel movement.

It helps to check the context: a “BM of 4.2” is a glucose, “no BM for 3 days” is constipation.

Weight in kilograms divided by height in metres squared; a simple screening measure of weight relative to height.

A US blood panel of glucose, calcium, sodium, potassium, chloride, bicarbonate, BUN and creatinine.

A hormone released by stretched heart muscle; BNP or NT-proBNP helps assess suspected heart failure.

The pressure of blood in the arteries, written as systolic over diastolic in mmHg.

An estimate of the body’s outer surface in m², calculated from height and weight. Used to dose chemotherapy and some other drugs.

A US measure of urea in the blood, used with creatinine to assess kidney function and hydration.

Introduces the patient’s presenting complaint, e.g. “c/o chest pain”.

The chemical symbol for calcium; total calcium is often corrected for albumin. In notes “Ca” is also shorthand for cancer (carcinoma).

A routine blood test measuring red cells, haemoglobin, white cells and platelets. The UK equivalent is FBC.

Blood glucose measured from a finger-prick sample with a meter, usually in mmol/L (UK, Australia) or mg/dL (US).

An older term for heart failure with fluid congestion, still common in US notes.

Reduced kidney function or kidney damage lasting more than three months, staged mainly by eGFR.

The BMP plus liver tests, total protein and albumin.

A long-term lung disease with persistent airflow limitation, mostly caused by smoking.

In acute care CP usually means chest pain. In paediatric and neurology notes it often means cerebral palsy, so context matters.

Chest compressions with rescue breaths or ventilation, given during cardiac arrest.

A waste product from muscle, measured in blood to assess kidney function and to calculate eGFR and creatinine clearance.

A blood marker of inflammation that rises within hours in infection and many inflammatory conditions.

A cross-sectional X-ray scan, sometimes with intravenous contrast.

An older term for stroke: brain damage from a blocked or burst blood vessel.

A catheter whose tip lies in a large central vein, usually inserted in the neck, chest or groin, used for drugs, fluids and monitoring.

A plain X-ray of the chest, used to look at the lungs, heart size and line or tube positions.

A life-threatening complication of diabetes with high glucose, ketones and metabolic acidosis, usually from lack of insulin.

A group of conditions with chronically high blood glucose, mainly type 1 and type 2.

The term used in the UK for a recorded decision not to attempt CPR. The “attempt” makes clear that CPR is not always successful; all other treatment continues as planned.

A documented decision that cardiopulmonary resuscitation should not be attempted if the heart or breathing stops. It does not mean withholding other care. Many services now use DNAR or DNACPR instead.

A blood clot in a deep vein, usually in the leg, which can travel to the lungs.

Dx is shorthand for diagnosis; “DDx” means differential diagnosis. In Italian notes “dx” means right (destra).

A recording of the heart’s electrical activity, most often the standard 12-lead ECG.

The hospital department for unplanned and emergency care.

An estimate of kidney function calculated from serum creatinine, age and sex, in mL/min/1.73 m².

The US spelling of ECG, from the German “Elektrokardiogramm”.

A slower, non-specific marker of inflammation measured in mm per hour.

The tube placed through the mouth or nose into the trachea to secure the airway and allow mechanical ventilation.

UK and Australian name for the complete blood count (CBC).

The proportion of oxygen in the gas the patient breathes in, from 0.21 (room air) up to 1.0 (100% oxygen).

The unit of mass for larger doses: 1 g = 1000 mg. Writing “500 mg” rather than “0.5 g” avoids decimal-point errors.

A score from 3 to 15 that assesses level of consciousness from eye, verbal and motor responses.

Short for drops, used for oral or eye drops and for gravity infusion sets (gtt/min). Drop size depends on the giving set’s drop factor.

Latin: guttae

The oxygen-carrying protein in red blood cells; a low value indicates anaemia. Reported in g/L or g/dL.

Reflects average blood glucose over roughly the previous 2–3 months; reported in mmol/mol or %.

A condition in which the heart cannot pump enough blood to meet the body’s needs, causing breathlessness and fluid retention.

A diabetic emergency with very high glucose, severe dehydration and high serum osmolality, usually without significant ketosis.

The number of heartbeats per minute.

A blood test for heart muscle injury, measured as troponin I (hs-cTnI) or T (hs-cTnT), usually repeated over a few hours in suspected heart attack.

Persistently raised blood pressure. Common in past medical history lists.

The patient’s history, as in PMHx (past medical history) or DHx (drug history).

A record of all fluids going in (oral, IV, feeds) and coming out (urine, drains, vomit), used to work out fluid balance.

The hospital unit for patients needing organ support and close monitoring.

The injection goes into the skin itself, just under the surface, as in the tuberculin (Mantoux) test. In other contexts ID can also mean “infectious diseases” or “identification”.

The medicine is injected into a muscle, for example the deltoid, vastus lateralis or ventrogluteal site.

The medicine is breathed in, for example from a metered-dose or dry-powder inhaler. INH is also a common abbreviation for the antituberculosis drug isoniazid.

A standardised version of the prothrombin time, used mainly to monitor warfarin and other vitamin K antagonists.

Drugs and fluids are given into the bone marrow through a special needle, usually in emergencies when IV access cannot be obtained quickly.

The UK name for the intensive care unit.

The medicine or fluid is given directly into a vein, as a bolus, an intermittent infusion or a continuous infusion.

In UK and Australian nursing IVC often means a peripheral intravenous cannula. In anatomy and imaging it means the inferior vena cava.

A drug given by injecting it directly into a vein or IV line over a short time, usually seconds to a few minutes. In radiology, IVP can also mean intravenous pyelogram.

A small-volume intermittent infusion, such as an antibiotic, connected to a port on an existing IV line. Mostly a US term.

The chemical symbol for potassium; both high and low serum potassium can cause dangerous heart rhythms.

1000 grams. Body weight in kg is the basis for many weight-based doses and scores.

The SI unit of pressure. UK, European and Australian blood gas reports often give PaO₂ and PaCO₂ in kPa (1 kPa ≈ 7.5 mmHg).

A very slow infusion rate used only to keep an IV cannula from clotting. It is advisable to write the exact rate on the order all the same.

1000 mL. Used for large fluid volumes and for oxygen flow (L/min).

A group of blood tests such as ALT, AST, ALP, GGT, bilirubin and albumin, used to look for liver injury or dysfunction.

A group of injectable anticoagulants, such as enoxaparin, usually given subcutaneously to prevent or treat blood clots.

Can mean either loss of consciousness (e.g. “head injury, no LOC”) or level of consciousness, so the context matters.

Latin for “in the morning”, used mainly on UK and Australian charts for a once-daily morning dose.

Latin: mane

The average pressure in the arteries over one cardiac cycle, used as a guide to organ perfusion.

The chart, paper or electronic, where each prescribed dose is recorded as given, withheld or refused.

One millionth of a gram, or one thousandth of a milligram. Written “mcg” rather than “µg” to avoid confusion with mg.

A unit for electrolytes based on their electrical charge. Common in US potassium and sodium orders; for monovalent ions such as K⁺ and Na⁺, 1 mEq equals 1 mmol.

One thousandth of a gram. The most common unit for drug doses.

The chemical symbol for magnesium; low levels are common and often accompany low potassium. Not the same as mg (milligram).

A heart attack: death of part of the heart muscle due to blocked blood supply.

One thousandth of a litre, the standard unit for liquid medicine and fluid volumes. Equal to one cubic centimetre (cc).

The unit used for blood pressure and many other clinical pressures.

One thousandth of a mole, the amount-of-substance unit used for electrolytes and many lab results (e.g. mmol/L).

Imaging that uses a strong magnetic field instead of X-rays; metal implants and devices are checked beforehand.

A common shorthand in notes and drug charts, for example as the indication for an antiemetic.

The chemical symbol for sodium; serum sodium is the main electrolyte determining water balance.

In UK notes NAD usually means “no abnormality detected” on examination; in US notes it often means “no acute distress”.

UK and Australian equivalent of NPO: the patient must not take any food or drink by mouth.

The medicine is turned into a fine mist and inhaled through a mask or mouthpiece, as with salbutamol or saline nebulisers.

A track-and-trigger score built from routine observations (respiratory rate, SpO₂, oxygen use, blood pressure, pulse, consciousness and temperature) that helps you spot a deteriorating patient. NEWS2 is the current UK version.

A tube passed through the nose into the stomach, used for feeding, giving medicines or draining the stomach. Checking the tube position before use is advisable.

Recorded when the patient has no known allergies to medicines. NKA (no known allergies) also covers food and other allergens.

Latin for “at night”, used mainly on UK and Australian drug charts for a dose given once in the evening or at bedtime.

Latin: nocte

The patient must not eat or drink anything, typically before surgery, procedures or when swallowing is unsafe. It is advisable for the order to say whether oral medicines are still allowed.

Latin: nil per os

A class of pain and anti-inflammatory medicines such as ibuprofen, naproxen and diclofenac. Relevant to kidney function, bleeding risk and stomach protection.

A heart attack confirmed by a troponin rise but without ST elevation on the ECG.

UK and Australian ward term for a set of vital signs: pulse, blood pressure, respiratory rate, oxygen saturation, temperature and consciousness.

The room where surgery takes place; in the UK and Australia it is called “theatre”.

A medicine you can buy without a prescription. It is worth asking about them when taking a drug history: patients often forget to mention them.

p.c. means “after meals”: the medicine is given after eating, often to reduce stomach upset or to match the timing of food.

Latin: post cibum

p.r.n. means “as needed”: the medicine is given only when required, for example for pain or nausea, not at fixed times. A good PRN order states the reason, the minimum interval and the maximum dose in 24 hours.

Latin: pro re nata

The oxygen tension in arterial blood, measured on a blood gas in mmHg or kPa.

Most often a pulmonary embolism, a clot blocking an artery in the lungs. In history-and-examination notes PE can also mean physical examination.

A feeding tube placed through the abdominal wall into the stomach with the help of an endoscope, used for long-term enteral nutrition and medicines.

A long, thin catheter inserted in an arm vein with its tip in a large central vein, used for longer courses of IV therapy.

The platelet count, part of the full blood count; relevant to bleeding risk and to heparin therapy.

PO means by mouth: the medicine is swallowed. It is the most common route abbreviation on drug charts.

Latin: per os

ISMP advises against writing “per os” because “os” can be read as OS, the left eye. “PO”, “by mouth” or “orally” are clearer.

A class of drugs that reduce stomach acid, such as omeprazole and pantoprazole.

The medicine is given into the rectum, for example as a suppository. In other contexts PR can also mean “pulse rate” or the PR interval on an ECG.

Latin: per rectum

A clotting test of the extrinsic pathway, reported in seconds and usually alongside the INR. In other contexts PT can mean physiotherapy or patient.

The medicine is given into the vagina, for example a pessary or cream. In notes PV also appears in “PV bleeding” (vaginal bleeding).

Latin: per vaginam

q.d.s. means four times a day. It is the British form of q.i.d.

Latin: quater die sumendum

q.i.d. means four times a day. It is not quite the same as “every 6 hours” (q6h), which spreads the doses evenly around the clock.

Latin: quater in die

q12h means every 12 hours around the clock: 2 doses in 24 hours. Unlike “twice a day”, the interval stays fixed through the night.

Latin: quaque duodecima hora

q4h means every 4 hours around the clock: 6 doses in 24 hours. Unlike “6 times a day”, the interval stays fixed through the night.

Latin: quaque quarta hora

q6h means every 6 hours around the clock: 4 doses in 24 hours. Unlike “four times a day”, the interval stays fixed through the night.

Latin: quaque sexta hora

q8h means every 8 hours around the clock: 3 doses in 24 hours. Unlike “three times a day”, the interval stays fixed through the night.

Latin: quaque octava hora

In physiotherapy and nursing, range of motion of a joint. In obstetrics, rupture of the membranes (waters breaking), e.g. SROM for spontaneous rupture.

The point during resuscitation when a pulse and effective heart rhythm return.

The number of breaths per minute, one of the earliest signs of deterioration.

The symbol at the top of a prescription, from the Latin “take”. In notes it is also used loosely for “treatment” or “therapy”.

Latin: recipe

A structured method for handing over or escalating concerns about a patient, clearly and concisely.

Introduces the directions for use on a prescription, i.e. what the pharmacist should write on the label (dose, route, frequency).

Latin: signa

The medicine is placed under the tongue and absorbed through the lining of the mouth, as with glyceryl trinitrate spray or tablets.

A structure for writing clinical notes: what the patient reports, what you find, your assessment, and the plan.

A common note for breathlessness, also written SOBOE (shortness of breath on exertion).

The percentage of haemoglobin carrying oxygen, measured non-invasively with a pulse oximeter.

STAT means now: a one-off dose, test or request to be carried out immediately. Common in emergency and acute care.

Latin: statim

A heart attack with ST elevation on the ECG, usually from a fully blocked coronary artery; it needs urgent reperfusion.

The form recommended by ISMP for the subcutaneous route, in place of SC, SQ or sub q.

Usually means symptoms; in some settings it means surgery. In Italian notes “sx” means left (sinistra).

Body temperature, recorded in °C (or °F in the US), often with the site (oral, tympanic, axillary). Italian charts write TC, which also means a CT scan.

t.d.s. means three times a day. It is the British form of t.i.d.

Latin: ter die sumendum

t.i.d. means three times a day, usually spread across the waking day. UK charts write “t.d.s.” instead.

Latin: ter in die

Diabetes caused by autoimmune destruction of insulin-producing cells; insulin treatment is always required.

The most common form of diabetes, linked to insulin resistance; treated with lifestyle measures, oral drugs, injectables or insulin.

Brief stroke-like symptoms that resolve fully, usually within an hour; a warning sign of future stroke.

Same meaning as KVO: a minimal infusion rate that keeps the IV line open. It is advisable to specify the rate in mL/h.

The medicine is applied to the skin or a mucous membrane, such as creams, ointments and gels.

Complete nutrition given intravenously, usually through a central line, when the gut cannot be used.

The main screening test for thyroid function; it is high in most hypothyroidism and low in most hyperthyroidism.

UK hospital term for the medicines a patient takes home at discharge, and for the prescription that lists them (also called TTA, “to take away”).

Usually means treatment or therapy, but in some notes it means transplant (or transfusion), so context matters.

A UK kidney panel: sodium, potassium, urea and creatinine, often with eGFR.

Imaging with sound waves, used at the bedside and in radiology, for example for abdominal scans or guiding cannulation.

An infection anywhere in the urinary tract, from bladder (cystitis) to kidney (pyelonephritis). Careful: in Italian, UTI means intensive care unit.

A blood gas test on venous blood, useful for pH, bicarbonate, lactate and electrolytes but not for assessing oxygenation.

The umbrella term for DVT and PE; often used in “VTE prophylaxis” and VTE risk assessment.

The white blood cell count, part of the CBC/FBC; raised or lowered values can point to infection, inflammation or bone marrow problems.

WNL means within normal limits: the finding or result is in the normal range. Critics joke that it stands for “we never looked”, so it is better to record the actual values.