The HX medical abbreviation means history, and in clinical records it typically refers to the patient's health history: past illnesses, surgeries, family conditions and habits. You will usually see it in lower case as hx or Hx, often in the phrase hx of, which simply means history of.
It belongs to a set of shorthand built on the letter x, alongside Dx (diagnosis), Tx (treatment) and Sx (symptoms). Read on for the main types of history, how a typical note line breaks down, and what students should know when they write it themselves.
At a glance
Stands for
HistoryWritten as
Hx, hx, HX; hx of means history ofCommon pairings
PMHx, FHx, SHx, PSHxWhere you see it
Admission notes, clinic notes, referral letters, discharge summariesSame pattern as
Do not confuse with
H/O, which also means history of in many notes
What the HX medical abbreviation stands for
History is the part of a medical record built from what the patient, or someone close to them, tells the clinician. It covers the story of the present problem, older conditions, past operations, medicines, allergies, family illnesses and lifestyle. Hx is just a quick way to write the word, and in medical terminology the hx medical abbreviation meaning stays the same whether it is typed in capitals or lower case.
When it appears alone, Hx usually means the overall history. With a qualifier in front of it, it narrows down: past medical, family, social or surgical. The phrase hx of works like a pointer, as in hx of asthma, telling the reader that the condition exists in the background, whether active or long settled.
Types of history in a medical record
| Shorthand | Full term | Typical content |
|---|---|---|
| HPI | History of present illness | Narrative of today's complaint, including onset, duration and severity |
| PMH or PMHx | Past medical history | Long term conditions such as high blood pressure or asthma |
| PSH or PSHx | Past surgical history | Operations and approximate timing |
| FHx | Family history | Conditions in parents, siblings and children |
| SHx | Social history | Tobacco and alcohol use, job, home setup |
Together these form the history half of the H and P, the history and physical exam that opens most hospital stays.
Reading hx of in a real note
Most notes open with a one line summary that leans heavily on this shorthand.
Emergency department note: "58 yo M with hx of HTN and DM2 presents with chest pain x 2 hrs." Read aloud: a 58 year old man with a history of high blood pressure and type 2 diabetes came in with chest pain that started two hours ago. Here hx of tells the reader what was already known before today.
Clinic note: "FHx: mother with breast cancer. SHx: never smoker, works in retail." These short labels sort background facts into tidy drawers the next clinician can scan quickly.
History medical abbreviation and the x family
Medicine uses a handful of two letter terms that end in x. The first letter is the whole key to telling them apart.
- Hx: history
- Dx: diagnosis, the name of the condition
- Tx: treatment, or in some settings transplant
- Rx: prescription or therapy
- Sx: symptoms, and in surgical notes sometimes surgery
- Fx: fracture
- Px: prognosis, or physical exam in some notes
Because a few of these carry more than one meaning, a clinician who is unsure what a colleague meant will often ask rather than guess.
Why a good history matters to patients
Many diagnoses rest more on the history than on any scan. The questions about when symptoms started, what makes them worse, which medicines you take and what runs in your family shape which tests are ordered and which are skipped. A clear history also prevents repeat testing and helps avoid medicines that clash with existing conditions.
Bringing a written list of conditions, past surgeries, current medicines and allergies to an appointment makes your history more complete. If a portal note says hx of something you do not recognize, that is a fair question to bring to your next visit.
Tips for students writing Hx in charts
Scribes and nursing students write this shorthand constantly. Keep it lower case or title case to match your facility, follow it with of when naming a condition, and avoid stacking unexplained abbreviations after it. Many facilities publish an approved abbreviation list; terms outside it should be spelled out. Writing history of in full is never wrong and is often clearer in letters to patients.
More admission and progress note terms are grouped on the nursing and chart notes page.
Consider this a general guide to the shorthand. Questions about what is listed in your own history can go straight to whoever wrote that note.
Frequently asked questions
What does hx mean in medical terms?
Hx means history. In a chart it usually refers to the patient's medical background, and hx of means history of, as in hx of asthma.
What is the medical abbreviation for history of?
The most common forms are hx of and H/O. Both introduce a condition the patient has had or still has.
What is the difference between Hx and PMH?
Hx covers history as a whole. PMH, or PMHx, is one specific part of it: past medical history, the list of earlier and ongoing conditions.
Does hx of mean the condition is gone?
Not necessarily. It only says the condition is part of the background. It may be ongoing, controlled or resolved, and the rest of the note usually explains which.
Why do so many chart terms finish with the letter x?
Writers adopted a short pattern of a letter plus x for common words, so Hx, Dx, Tx and Sx mirror the much older Rx. It is a convention for speed rather than a formal rule.