The PD medical abbreviation carries several standard meanings; the three you will meet most are Parkinson disease, peritoneal dialysis and progressive disease, the oncology term for cancer that has grown or spread. No single one wins everywhere, so the clinic, the specialty and the words around the letters decide.
A neurology note that mentions tremor and slowness means Parkinson disease. A kidney note about nightly exchanges and a catheter in the belly means peritoneal dialysis. A cancer scan report that compares tumor sizes means progressive disease. Less often PD can also stand for personality disorder, panic disorder, pupillary distance for eyeglasses or pharmacodynamics. This guide takes the meanings one at a time, each with a sample line.
At a glance
Stands for
Parkinson disease; peritoneal dialysis; progressive diseaseOther meanings
Personality disorder; panic disorder; pupillary distance; pharmacodynamicsSpecialty
Neurology, nephrology, oncology, psychiatry, eye care, pharmacologyWhere you see it
Problem lists, dialysis orders, scan reports, trial summariesOncology partners
CR, PR and SD, other tumor response categoriesDo not confuse with
HD (hemodialysis) and PPD (a skin test for tuberculosis)
Sorting out the PD medical abbreviation by setting
The quickest way to read PD is to check the author's specialty and the surrounding words.
| Meaning | Typical setting | Clues nearby |
|---|---|---|
| Parkinson disease | Neurology, primary care, geriatrics | Tremor, rigidity, slow movement, levodopa |
| Peritoneal dialysis | Nephrology, dialysis units | Exchanges, dwell, PD catheter, peritonitis |
| Progressive disease | Oncology, clinical trials | Scan comparison, tumor sizes, response categories |
| Personality or panic disorder | Psychiatry, behavioral health | Mental status findings, therapy plans |
| Pupillary distance | Eye care, optical orders | Measurement in millimeters on a lens order |
PD medical abbreviation progressive disease in oncology
Cancer teams judge treatment by comparing scans over time. Under a widely used set of solid tumor response rules, results fall into four groups: complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). Progressive disease usually means the measured tumors grew by at least 20 percent in total size, or new areas of cancer appeared.
Scan report: "CT C/A/P: new liver lesions. Response per RECIST: PD." CT C/A/P is CT imaging covering chest, belly and pelvis, lesions are abnormal spots, and RECIST names the response rules. PD here means the cancer has progressed.
A PD result often prompts the team to talk about changing treatment. In trial papers, progression free survival, written PFS, counts the time until PD or death.
Parkinson disease in neurology notes
Parkinson disease is a slowly progressing brain condition caused by loss of cells that make dopamine, a chemical messenger that helps control movement. Main signs include a resting tremor, stiffness, slowness of movement and problems with balance. Nonmovement symptoms such as constipation, sleep changes, loss of smell and mood changes are common too.
A history line might read "PD dx 6 yrs, on carbidopa levodopa, falls x 2." Notes may also say parkinsonism, a broader term for the same movement pattern from various causes. Related neurology shorthand such as MS often sits in the same problem lists.
Peritoneal dialysis in kidney care
Peritoneal dialysis is a way to clean the blood when the kidneys fail, using the peritoneum, the thin membrane lining the abdomen, as a natural filter. A soft tube placed in the abdomen lets cleansing fluid flow in, rest for a set time, then drain out with waste and extra water. Many people do it at home, using manual exchanges in daytime or an automated cycler while asleep.
Dialysis order: "Continue home PD nightly via cycler, monitor for cloudy effluent." A cycler is the overnight machine, and effluent is the drained fluid. Cloudy fluid can signal peritonitis, an infection of the lining.
It is an alternative to hemodialysis, written HD, for people with ESRD.
Lookalikes and charting tips
Because PD carries so many meanings, many teaching programs ask learners to spell out the term the first time it appears in a note, then use PD after. Watch for these near misses.
- PPD: a tuberculosis skin test, or in some notes packs per day for smoking history.
- PDA: patent ductus arteriosus, a heart vessel that stays open after birth.
- PT: physical therapy or prothrombin time, depending on context.
More condition terms appear on the diagnosis abbreviations hub.
Two letters can carry many senses, as shown above. When PD in your own chart could mean more than one thing, ask its author to clarify which sense was intended.
Frequently asked questions
What does PD mean in oncology?
In oncology PD usually means progressive disease, meaning the cancer has grown, or new spots have appeared, when follow up scans are set beside earlier ones. It is one of four standard response categories, alongside complete response, partial response and stable disease.
What does PD stand for in neurology?
In neurology PD almost always means Parkinson disease, a movement disorder caused by loss of dopamine producing brain cells.
What is the difference between PD and HD in kidney care?
Both are forms of dialysis. PD, peritoneal dialysis, relies on the peritoneum, the inner belly lining, to filter blood and is often done at home, while HD, hemodialysis, filters blood through a machine, usually at a dialysis center.
How can I tell which PD my chart means?
Look at the specialty and the nearby words. Tremor points to Parkinson disease, exchanges or a belly catheter point to dialysis, and scan comparisons point to progressive disease. When in doubt, ask the care team.