Medical Prescription, What is Medical Prescription?

A prescription is a health care programme that governs the plan of care for an individual patient and is implemented
by a qualified practitioner.

A qualified practitioner might be a physician, dentist, nurse practitioner, pharmacist, psychologist, or other health care

Prescriptions may include orders to be performed by a patient, caretaker, nurse, pharmacist, physician, other therapist,
or by automated equipment, such as an intravenous infusion pump.

Formerly, prescriptions often included detailed instructions regarding compounding of medications but as medications
have increasingly become pre packaged manufactured products, the term "prescription" now usually refers to an order
that a pharmacist dispense and that a patient take certain medications.

Prescriptions have legal implications, as they may indicate that the prescriber takes responsibility for the clinical care of
the patient and in particular for monitoring efficacy and safety.

As medical practice has become increasingly complex, the scope of meaning of the term "prescription" has broadened
to also include clinical assessments, laboratory tests, and imaging studies relevant to optimizing the safety or efficacy
of medical treatment.

Format and Definition

Prescriptions are typically handwritten on preprinted prescription forms that are assembled into pads, or alternatively
printed onto similar forms using a computer printer or are in an electronic format.

Preprinted on the form is text that identifies the document as a prescription, the name and address of the prescribing
provider and any other legal requirement such as a registration number (e.g. DEA Number in the United States).

Unique for each prescription is the name of the patient. In the United Kingdom and Ireland, the patient's name and
address must also be recorded.

Each prescription is dated and some jurisdictions may place a time limit on the prescription.
There is the specific "recipe" of the medication and the directions for taking it is a symbol meaning "prescription".

It is sometimes transliterated as "Rx" or just "Rx".
This symbol originated in medieval manuscripts as an abbreviation of the Late Latin verb recipe, the imperative form
of recipere, "to take" or "take thus".

Literally, the Latin word recipe means simply "Take." and medieval prescriptions invariably began with the command
to "take" certain materials and compound them in specified ways.

Today, when a medical practitioner writes a prescription beginning with , he or she is completing the command.
Folk theories about the origin of the symbol note its similarity to the Eye of Horus,
or to the ancient symbol for Zeus or Jupiter, gods whose protection may have been sought in medical contexts.

The word "prescription", from "pre-" ("before") and "script" ("writing, written"), refers to the fact that the prescription is an
order that must be written down before a compound drug can be prepared. Those within the industry will often call
prescriptions simply "scripts".

The fact that a prescription instructs someone to "take" rather than "give" is not a trivial distinction, but makes clear it is
directed at the patient, and is not directly an instruction to anyone else.
In certain states medical marijuana legislation has been drafted calling for a health care professional's written or oral

"recommendation", in the belief that a written one would be legally
distinguishable from a prescription, but since written advice to a patient is what a prescription is, that belief is mistaken.

Jurisdictions may adopt a statutory definition of "prescription" which is applicable as a term of art only to the operation of
that statute but the general legal definition of the word is this broad one.


Both pharmacists and prescribers are regulated professions in most jurisdictions.
A prescription as a communications mechanism between them is also regulated and is a legal document.

Regulations may define what constitutes a prescription, the contents and format of the prescription and how prescriptions
are handled and stored by the pharmacist.

Many jurisdictions will now allow faxed or phone prescriptions containing the same information. Exhibit A below illustrates
the legal definition of a prescription.

Many brand name drugs have cheaper generic drug substitutes that are therapeutically and biochemically equivalent.
Prescriptions will also contain instructions on whether the prescriber will allow the pharmacist to substitute a generic
version of the drug. This instruction is communicated in a number of ways.

In some jurisdictions, the preprinted prescription contains two signature lines: one line has "dispense as written" printed
underneath; the other line has "substitution permitted" underneath.

Some have a preprinted box "dispense as written" for the prescriber to check off.
Other jurisdictions the protocol is for the prescriber to handwrite one of the following phrases: "dispense as written",

"DAW", "brand necessary", "do not substitute", "no substitution", "medically necessary", "do not interchange".
In other jurisdictions may they use completely different languages, never mind a different formula of words. In some
jurisdictions, it may be a legal requirement to include the age of child on the prescription.

For pediatric prescriptions some advise the inclusion of the age of the child if the patient is less than twelve and the
age and months if less than five. Adding the weight of the child is also helpful.

Prescriptions often have a "label" box.
When checked, the pharmacist is instructed to label the medication.

When not checked, the patient only receives instructions for taking the medication and no information about the
prescription itself. Some prescribers further inform the patient and pharmacist by providing the indicator for the
medication; i.e. what is being treated.

This assists the pharmacist in checking for errors as many common medications can be used for multiple medical

Some prescriptions will specify whether and how many "repeats" or "refills" are allowed; that is whether the patient may
obtain more of the same medication without getting a new prescription from the medical practitioner.

Regulations may restrict some types of drugs from being refilled.
In group practices, the preprinted portion of the prescription may contain multiple prescribers' names.

Prescribers typically circle themselves to indicate who is prescribing or there may be a checkbox next to their name.


When filled by a pharmacist, as a matter of business practice, the pharmacist may write certain information right on the
prescription.This may also be mandated by legislation.

Information such as the actual manufacturer of the drug and the date the medication was dispensed may be written
right onto the prescription.

Legislation may require the pharmacist to sign the prescription. In computerized pharmacies, all such information is
printed and stapled to the prescription.

Sometimes such information is printed onto labels and the labels affixed right onto the prescription.

When filled by the pharmacist, prescriptions are typically assigned a "prescription number"
(often abbreviated "Rx" in the US) that is unique to the pharmacy that filled the prescription.

The prescription number is written right on the prescription by the pharmacist.
The prescription number has the practical purpose of uniquely identifying the prescription later on while filed
(both manual and electronic).

The prescription number is also put on the label on the dispensed medication.
The patient may be required to reference the prescription number for refills and drug insurance claims.
There may also be a legal requirement for prescription numbers for subsequent identification purposes.

As a legal document, some jurisdictions will mandate the archiving of the original paper prescription in the pharmacy.

Often the patient cannot take the original prescription with them.
Some jurisdictions may entitle patients to a copy.
The retention period varies but can be as long as ten years

See Exhibit B for sample legislation governing the archiving of prescriptions.
Once the retention period has passed, privacy legislation may dictate what can be done with the original paper prescription.

Legislation may also dictate what happens to the prescriptions if the pharmacy closes or is sold. For example, if the
pharmacy goes out of business, the pharmacist may be required to return the prescription to the patient, to the next
closest pharmacy or to the governing body for pharmacists.

Prescriptions for non-narcotic drugs may also be "transferred" from one pharmacy to another for subsequent repeats
to be dispensed from another pharmacy.

The physical piece of paper that is the prescription is not transferred, but all the information on it is transferred from one
pharmacy to another.

Legislation may dictate the protocol by which the transfer occurs and whether the transfer needs to be noted on the original
paper prescription.

It is estimated that three billion prescriptions were written in the United States in 2002.
This number grew from 1.5 billion in 1989 and is expected to continue to grow.

Rx security  forgeries and prevention

Prescriptions are sometimes forged because many narcotics are cheaper and safer as prescription drugs than as street
drugs. Forgery takes many forms: Prescription pads are sometimes stolen, amounts may be altered on legitimate
prescriptions,  call back numbers may be falsified and phoned or faxed prescriptions faked.

To make photocopying prescriptions more difficult, some medical practitioners use prescription pads that contain security
measures similar to those used on bank checks.

These security measures may be mandated by law-see Exhibit C for sample legal specifications. Legislation may mandate
that only certain printers may print prescriptions.

New Jersey, for example, requires that only state approved printers may be used to print official "New Jersey Prescription
Prescribers can make it more difficult to forge dosages and quantities by writing out numbers in words. Again, this may be
mandated by law.
Some jurisdictions help control stolen prescriptions by requiring special "triplicate prescriptions" for certain classes of drugs.

Blank triplicates are only available from the regulating agency and are individually numbered.
The medical practitioner retains a copy, the second and third copies are given to the patient to give to the pharmacist.

The pharmacist retains the second copy and the third copy is submitted to the regulating agency. The regulating agency
can issue lists of forged prescriptions that pharmacists can check. In this example, the prescription's validity is further
limited to 72 hours from issuance.

California has recently replaced triplicate forms with new forms that are impossible to photocopy or fax: the background is
printed with repetitions of the word void in a color that shows up as black on a photocopy.

States have various laws making theft of prescription blanks or forgery of prescriptions criminal offenses and/or providing
special treatment for these offenses.

When forgery is suspected, pharmacists will call the medical practitioner to verify the prescription.
Forged prescriptions are no longer considered medical documents and doctor-patient confidentiality rules no longer apply.

Who can write prescriptions (that may legally be filled with prescription-only items)

Any jurisdiction that allows freedom of written communication generally must therefore allow anybody to write a
prescription to anybody, inasmuch as the prescription itself is just written advice.

Therefore "who can write prescriptions" will be explained below as shorthand for "whose prescriptions may legally be
filled with items restricted to dispensing via the order of certain persons".

National or local (i.e. state or provincial) legislation governs who can write a prescription.
In North America, physicians (either M.D. or D.O.) have the broadest prescriptive authority.

All 50 States and the District of Columbia allow licensed certified Physician Assistants (PAs) prescription authority
(with some limitations to controlled substances).

All 50 States allow registered certified Nurse Practitioners and other advanced-practice nurses
(such as certified nurse-midwives) prescription power (with some states including limitations to controlled substances).

Many other healthcare professions also have prescriptive authority related to their area of practice. Veterinarians, dentists, and
podiatrists have prescribing power in all 50 states and the District of Columbia.
Clinical pharmacists are allowed to prescribe in some states through the use of a drug formulary or collaboration

Florida Pharmacists can write prescriptions for a limited set of drugs.
In all states, optometrists prescribe medications to treat certain eye diseases, and also issue spectacle and
contact lens prescriptions for corrective eyewear.

Several states have passed RxP legislation, allowing clinical psychologists (PhD's or PsyD's) who are registered as medical
psychologists and have also undergone specialized training in script-writing to prescribe drugs to treat emotional and mental

Physicians who practice chiropractic medicine may have the ability to write a prescription, depending on scope of
practice laws in a jurisdiction.


Prescriptions, when handwritten, are notorious for being often illegible. In the US, medical practitioners' sloppy handwriting
kills more than 7,000 people annually, according to a July 2006 report from the National Academies of Science's Institute
of Medicine (IOM).

Historically, physicians used Latin words and abbreviations to convey the entire prescription to the pharmacist.
Today, many of the abbreviations are still widely used and must be understood to interpret prescriptions.

At other times, even though some of the individual letters are illegible, the position of the legible letters and length of the
word is sufficient to distinguish the medication based on the knowledge of the pharmacist.

When in doubt, pharmacists call the medical practitioner.
Some jurisdictions have legislated legible prescriptions (e.g. Florida).

Some have advocated the elimination of handwritten prescriptions altogether and computer printed prescriptions are
becoming increasingly common in some places.

Conventions for avoiding ambiguity

Over the years, prescribers have developed many conventions for prescription-writing, with the goal of avoiding
ambiguities or misinterpretation.

These include:

Careful use of decimal points to avoid ambiguity:
Avoiding unnecessary decimal points: a prescription will be
written as 5 mL instead of 5.0 mL to avoid possible misinterpretation of 5.0 as 50.

Always using zero prefix decimals: e.g. 0.5 instead of .5 to avoid misinterpretation of .5 as 5.
Avoiding trailing zeros on decimals: e.g. 0.5 instead of .50 to avoid misinterpretation of .50 as 50.
"mL" is used instead of "cc" or "cm" even though they are technically equivalent to avoid misinterpretation of 'c' as '0'
or the common medical abbreviation for "with" (the Latin "cum"), which is written as a 'c' with a bar above the letter.

Further, cc could be misinterpreted as "c.c.", which is an uncommonly used abbreviation for "take with meals"
(the Latin "cum cibo").

Directions written out in full in English
(although some common Latin abbreviations are listed below).

Quantities given directly or implied by the frequency and duration of the directions.
Where the directions are "as needed", the quantity should always be specified.

Where possible, usage directions should specify times (7 am, 3 pm, 11 pm) rather than simply frequency
(three times a day) and especially relationship to meals for orally consumed medication.

The use of permanent ink

Avoiding unspecified prn or "as needed" instructions-instead, specific limits and indicators are provided e.g.
"every 3 hours prn pain."

For refills, the minimum duration between repeats and number of repeats should be specified.
Providing the indication for all prescriptions even when obvious to the prescriber, so that the pharmacist may identify possible

Avoiding units such as "teaspoons" or "tablespoons."
Writing out numbers as words and numerals ("dispense 30 (thirty)") as in a bank draft or cheque.
The use of apothecary/avoirdupois units and symbols of measure -- pints (O), ounces, drams , scruples, grains (gr), and
minims -- is discouraged given the potential for confusion.

For example, the abbreviation for a grain ("gr") can be confused with the gram, abbreviated g, and the symbol for minims,
which looks almost identical to an 'm', can be confused with micrograms or metres.

Also, the symbols for ounce  and dram can easily be confused with the numeral '3', and the symbol for pint  can be easily
read as a '0'.
Given the potential for errors, metric equivalents should always be used.

The use of the degree symbol (°), which is commonly used as an abbreviation for hours
(e.g., "q 2-4°" for every 2 - 4 hours), should not be used, since it can be confused with a '0'.

Further, the use of the degree symbol for primary, secondary, and tertiary (1°, 2°, and 3°) is discouraged, since the
former could be confused with quantities (i.e. 10, 20 and 30, respectively).


See list of abbreviations used in medical prescriptions.
Many abbreviations are derived from Latin phrases.

Hospital pharmacies have more abbreviations, some specific to the hospital.
Different jurisdictions follow different conventions on what is abbreviated or not.
Prescriptions that don't follow area conventions may be flagged as possible forgeries.

Some abbreviations which are ambiguous, or which in their written form might be confused with something else, are not
recommended and should be avoided.
These are included in a separate list in Appendix 1.
However, all abbreviations carry an increased risk for confusion and misinterpretation and should be used cautiously.

In Continental Europe

In continental Europe, prescriptions differ from their counterparts in the Anglosphere.
With the exception of patient directions, they are written out entirely in abbreviations deriving from the Latin language.
Furthermore, a larger proportion of prescriptions are compounded, and appropriate abbreviations and phrases exist for this.

Parts of a European prescription

A continental European prescription consists of three parts:
the inscritio, also known as the superscriptio, is the header of the prescription and consists of the patient's name, address,
and identity document number, as well as the identifying number of the patient's private health insurance company, if

applicable; and the praescriptio is the prescription itself; that is, directions to the dispensing pharmacist to supply medication,
made up of the following: the invocatio, consisting of the abbreviation Rp; this is analogous to the Rx used in the

Anglosphere, and stands for recipe, Latin for take [from the shelf]; and
the ordinatio, also known as the compositio, which consists either of the brand name, strength,
and number and type of dosage units of a particular drug, or else of directions written entirely in the Latin accusative case,
with the exception of ingredient names, written in the genitive case.

Masses are written in grammes, without the unit name.
The compositio is followed by the subscriptio, which consists of the directions according to which the medicament is to
be prepared.
An important part of this is the signatura, which is directed towards the patient and explains how to use the medication.
Unlike the rest of the prescription, the signatura is written in the national vernacular.

Other conventions

Should a patient require a dosage in excess of the maximum as established by the appropriate governmental body, this is
marked by an exclamation mark and the highest recommended dosage in Latin.
If this is not done, it is the responsibility of the pharmacist to contact the doctor as to dose requirements, or amend the
dose to the highest recommended one.

In emergency situations, a prescription pad may not be available. In this situation, any piece of paper will do, provided it is
marked Periculum in mora!; that is, danger in delay
(other designations, such as Cito! or Statim!, are also used and understood).

Such ad-hoc prescriptions have a limited period of validity; typically, this is the day after the prescription is written.
A doctor may self-prescribe, or prescribe for his family; this is done by replacing the signatura by the Latin phrase pro manus
medici (for medical hands).

This is to be done with caution; certain drugs self-prescribed will arouse suspicion, and may result in investigation by the
medical board or another governmental body.
Brand-name drugs may be swapped for generics; if this is not wanted by the doctor, he may write dispense as written in
the local language on the prescription.

Non prescription drug prescriptions

Prescriptions are also used for things that are not strictly regulated as a prescription drug. Prescribers will often give
non-prescription drugs out as prescriptions because drug benefit plans may reimburse the patient only if the
over-the-counter medication is taken under the direction of a medical practitioner.

Conversely, if a medication is available over-the-counter, prescribers may ask patients if they want it as a prescription or
purchase it themselves.

Pharmacists may or may not be able to price the medication competitively with over-the-counter equivalents.
If the patient wants the medication not under prescription, the prescriber is usually careful to give the medication name to
the patient on a blank piece of paper to avoid any confusion with a prescription.

This is applied to non-medications as well.
For example, crutches, and registered massage therapy may be reimbursed under some health plans, but only if given
out by a prescriber as a prescription.

Prescribers will often use blank prescriptions as general letterhead.
Legislation may define certain equipment as "prescription devices".

Such prescription devices can only be used under the supervision of authorized personnel and such authorization is typically
documented using a prescription.

Examples of prescription devices include dental cement (for affixing braces to tooth surfaces), various prostheses,
gut sutures, sickle cell tests, cervical cap and ultrasound monitor.

In some jurisdictions, hypodermic syringes are in a special class of their own, regulated as illicit drug use accessories
separate from regular medical legislation.
Such legislation will often specify a prescription as the means by which one may legally possess syringes.

Related usage of the term prescription

Prescription may also be used as a short form for prescription drugs to distinguish from over-the-counter drugs.
In reference to the entire system of controlling drug distribution (as opposed to illicit drugs), "prescription" is often used as a
metaphor for healthy directions from a prescribing medical practitioner.

A green prescription is direction from a medical practitioner to a patient for exercise and healthy diet.


The concept of prescriptions dates back to the beginning of history.
So long as there were medications and a writing system to capture directions for preparation and usage, there were
Modern prescriptions are actually "extemporaneous prescriptions" from the Latin (ex tempore) for "at/from time".
"Extemporaneous" means the prescription is written on the spot for a specific patient with a specific ailment.

This is distinguished from a non-extemporaneous prescription which is a generic recipe for a general ailment.
Modern prescriptions evolved with the separation of the role of the pharmacists from that of the physician.

Today the term "extemporaneous prescriptions" is reserved for "compound prescriptions" which requires the pharmacist
to mix or "compound" the medication in the pharmacy for the specific needs of the patient.
Predating modern legal definitions of a prescription, a prescription traditionally is composed of four parts: a "superscription",
"inscription", "subscription" and "signature".

The superscription section contains the date of the prescription and patient information (name, address, age, etc.).

The symbol  separates the superscription from the inscriptions sections. In this arrangement of the prescription, the is a
symbol for recipe or literally the imperative "take."

This is an exhortation to the pharmacist by the medical practitioner, I want the patient to have the following medication - in
other words, "take the following components and compound this medication for the patient."

The inscription section defines what is the medication.
The inscription section is further composed of one or more of:

a "basis" or chief ingredient indended to cure (curare)
an "adjuvant" to assist its action and make it cure quickly (cito)

a "corrective" to prevent or lessen any undesirable effect (tuto)
a "vehicle" or "excipient" to make it suitable for administration and pleasant to the patient (jucunde)

The "subscription" section contains dispensing directions to the pharmacist.
This may be compounding instructions or quantities.
The "signature" section contains directions to the patient  and is often abbreviated.

It also obviously contains the signature of the prescribing medical practitioner though the word "signature" has two distinct
meanings here and the abbreviations are sometimes used to avoid confusion.

Use of technology

As a prescription is nothing more than information among a prescriber, pharmacist and patient, information technology
can be applied to it.
Existing information technology is adequate to print out prescriptions.

Medical information systems in some hospitals do away with prescriptions within the hospital.
There are proposals to securely transmit the prescription from the prescriber to the pharmacist using smartcard or
the internet.

In the United Kingdom a project called the Electronic Transfer of Prescriptions (ETP) within the National Programme
for IT (NPfIT) is currently piloting such a scheme between prescribers and pharmacies.

Within computerized pharmacies, the information on paper prescriptions is recorded into a database.
Afterwards, the paper prescription is archived for storage and legal reasons.

A pharmacy chain is often linked together through corporate headquarters with computer networking.
Walgreens, for example, uses satellite technology to share patient information.
A person who has a prescription filled at one Walgreens can get a refill of that prescription at any other store in the chain, as
well as have their information available for new prescriptions at any walgreens.

Some online pharmacies also offer services to customers over the internet.
Walgreens' web site, for example, allows customers to order refills for medicine over the internet, and allows them to
specify the store that they will pick up the medicine from.

Their web site also allows consumers to look up their prescription history, and to print it out.
Many pharmacies now offer services to ship prescription refills right to the patient's home. CVS, for example, will ship
refills free of charge.

They also offer mail service where you can mail in a new, original prescription and a signed document, and they will
ship the filled prescription back to you.

Pharmacy information systems are a potential source of valuable information for pharmaceutical companies as it contains
information about the prescriber's prescribing habits.
Prescription data mining of such data is a developing, specialized field.

Many prescribers lack the digitized information systems that reduce prescribing errors.
To reduce these errors, some investigators have developed modified prescription forms that prompt the prescriber to
provide all the desired elements of a good prescription.

The modified forms also contain pre-defined choices such as common quantities, units and frequencies that the
prescriber may circle rather than write out.
Such forms are thought to reduce errors, especially omission and handwriting errors and are actively under evaluation.

See Also Articles About Drugs

General Articles Drugs
Home  |  Drugs A-Z  |  Drugs Side Effects  |  Drugs Article  |  Drugs Faq  | Health Article  |  About Site
Bookmark and Share