The NPO medical abbreviation means nothing by mouth: no food, no drinks and often no gum or candy until the order is lifted. It comes from the Latin nil per os, and it may be written NPO, npo, n.p.o. or N.P.O.
Most people first see it the night before a procedure, on a hospital whiteboard, or on a sign taped above a bed. It is the standard medical abbreviation for nothing by mouth, a quick order that everyone on the unit understands, and the NPO medical abbreviation meaning stays the same in hospitals, clinics and surgery centers. This guide covers what NPO usually allows and forbids, the common variations such as NPO except meds, and the questions worth asking when you or a family member is told to stop eating.
At a glance
Stands for
Nothing by mouthLatin origin
Nil per os, nothing through the mouthWritten as
NPO, npo, n.p.o., N.P.O.Where you see it
Pre-op instructions, diet orders, bedside signs, nursing handoffsOpposite order
Common add-ons
Except meds, with sips, after midnight, for procedure
What the NPO medical abbreviation tells the care team
NPO is a diet order, and the abbreviation in NPO nursing notes never refers to anything else. Instead of saying what a patient may eat, it says the patient may take nothing by mouth at all. On most units that includes solid food, all drinks, ice chips, gum and hard candy, unless the order says otherwise. Mouth care is still allowed and encouraged, because a dry mouth is uncomfortable and brushing teeth does not mean swallowing anything.
The order stays in place until a doctor, surgeon or other prescriber changes the diet. A nurse cannot simply decide that a patient looks well enough to eat, and the pharmacist checks the same order before sending oral medicines. Related orders such as HOB elevation for aspiration precautions often sit beside it. When the reason for fasting has passed, the order is usually advanced step by step, for example to clear liquids first and then to a full diet.
Why patients are made NPO
Fasting is rarely ordered for no reason. The most common reasons are these:
- Anesthesia and sedation. An empty stomach lowers the chance that stomach contents come back up and enter the lungs while a person is asleep or sedated.
- Some tests and procedures. Scopes of the stomach or bowel, certain scans with contrast, and some blood tests need an empty stomach to be safe or accurate.
- Swallowing problems. After a stroke or with severe weakness, a person may be kept NPO until a swallow check shows that food will not go down the wrong way.
- Bowel rest. Conditions such as a bowel blockage, severe pancreatitis or heavy vomiting may call for a pause in eating.
When fasting lasts longer than a short while, the team may give fluids through an IV line, and in some longer cases nutrition by vein such as TPN.
Reading common NPO orders
The bare letters are often followed by a few words that change the meaning a great deal. These are the versions seen most often.
| Order as written | What it usually means |
|---|---|
| NPO | Nothing at all by mouth until the order changes |
| NPO after midnight | Eat and drink normally until 12 at night, then stop |
| NPO except meds | Nothing by mouth, but scheduled pills are still given, usually with a small sip of water |
| NPO with sips | Small sips of water allowed, often only to take pills |
| NPO for procedure | Fasting tied to one planned test or operation, often lifted after it |
A nurse's handoff: "Bed 12 is NPO except meds for a scope in the morning." The patient gets no breakfast, but the morning blood pressure pill is still given with a sip of water as ordered.
How long before surgery do you stop eating?
Older advice told almost everyone to stop eating and drinking at midnight. Many hospitals now follow anesthesia guidelines that allow shorter fasts for healthy adults having planned surgery. Under those guidelines, clear liquids such as water are often allowed until about 2 hours before the procedure, a light meal until about 6 hours before, and a heavy or fatty meal usually needs about 8 hours.
These numbers are general patterns, not rules for any one person. Babies, people with diabetes, people with slow stomach emptying and people taking certain weight loss medicines may get different instructions. The written instructions from your own surgical team are the ones to follow, and if they are unclear, call the number on the sheet.
Nothing by mouth medical abbreviation and your medicines
The most common worry about NPO is what happens to regular medicines. Some are taken as usual with a sip of water, some are held the morning of a procedure, and some are adjusted ahead of time. Blood thinners, diabetes medicines and insulin are the ones most often changed, but the plan depends on the person and the procedure.
Do not skip or stop a medicine on your own because you were told to fast. Ask the surgeon, anesthesia team or pharmacist which ones to take and which to hold, and write the answer down.
This page explains a common chart order in general terms. Your own fasting and medicine plan comes from the team doing your procedure, so check any doubts with them or your pharmacist.
NPO in nursing and pharmacy work
As a nursing abbreviation, NPO is one of the first diet orders students learn, and it carries real duties. The nurse posts a sign, removes the meal tray, explains the reason to the patient and family, and checks with the prescriber about scheduled oral medicines. Intake and output are tracked, and mouth care is offered often.
Read as a pharmacy abbreviation, an NPO status can mean switching a pill to another route, such as IV, a patch or a suppository, so that treatment continues. Seeing NPO next to a long list of oral medicines is a cue to ask how each one should be handled. More orders and chart terms of this kind are gathered in our collection of nursing shorthand.
Frequently asked questions
What is the NPO meaning as a medical term?
In medical terminology, NPO means nothing by mouth. It comes from the Latin nil per os and is an order that a patient should not eat or drink until the order is changed.
Can you drink water when you are NPO?
Usually not, unless the order says NPO with sips or NPO except meds. Some surgery instructions allow clear liquids until a set time before arrival, so follow the exact wording your team gives you.
Can I brush my teeth if I am NPO?
In most cases yes, as long as you rinse and spit without swallowing. Mouth care is a normal part of nursing care for fasting patients.
What does NPO after midnight mean?
It means you may eat and drink as usual until midnight, then take nothing by mouth from that point until your procedure or until told otherwise. Many centers now give more specific times, so check your own instructions.
Is NPO the same as a clear liquid diet?
No. A clear liquid diet allows drinks such as water, broth and clear juice, while NPO allows nothing at all by mouth. Patients are often moved from NPO to clear liquids as a first step back to eating.