The RX medical abbreviation means prescription. It is usually written Rx, with a capital R and a small x, and it marks an order for a medicine or treatment written by a licensed prescriber. The symbol traces back to the Latin word recipe, meaning take, which opened prescriptions for centuries.
You will see Rx at the top of prescription pads and electronic prescriptions, on pharmacy signs and on medicine labels. In chart notes, some clinicians also use Rx to mean treatment or therapy in general. This page explains both uses, how a prescription is laid out, and how Rx fits with its look-alike cousins Dx, Tx and Hx.
At a glance
Stands for
Prescription; in notes, sometimes treatment or therapyLatin origin
Recipe, take (an instruction to the pharmacist)Written as
Rx, RX, a crossed R symbolWhere you see it
Prescriptions, pharmacy labels, medicine packages, chart notesRelated forms
Rx only on packages; OTC for over the counterDo not confuse with
Where the Rx symbol comes from
Old prescriptions began with the Latin word recipe, the command form of a verb meaning to take. It told the person preparing the medicine to take certain ingredients and combine them. Over time the word was shortened to an R with a line through its tail, which is the symbol still printed on pads today.
Some writers also connect the symbol to older traditions of healing marks, but the link to recipe is the explanation most reference works give. In modern use, the meaning is simply prescription.
How the RX medical abbreviation appears on a prescription
A written or electronic prescription follows a set layout. The Rx line names the drug and strength, and the Sig line, short for the Latin signa, tells the pharmacist what directions to print on the label.
| Part | What it holds |
|---|---|
| Rx | The medicine, strength and form, such as amoxicillin 500 mg capsules |
| Disp | How much to dispense, such as 30 capsules |
| Sig | Directions, such as 1 cap PO TID x 10 days |
| Refills | How many times it may be refilled |
| Prescriber details | Name, signature and license or registration numbers |
Label printed from that prescription: "Take 1 capsule by mouth three times daily for 10 days." The pharmacist turns the Rx and Sig shorthand into plain words, so the patient never needs to decode it. The medicine and amounts here only illustrate the format.
Rx only, OTC and what the labels mean
In the United States, medicines that need a prescription carry the phrase Rx only on the package. It means the product may be dispensed only on a valid order from a licensed prescriber. Medicines sold without a prescription are called over the counter, written OTC.
Some medicines exist in both forms, often with a lower strength sold over the counter and a higher strength by prescription. Pharmacy staff can explain which version a person has and whether it may interact with anything else they take.
Rx as treatment in chart notes
Chart writers have a habit of ending short forms with an X, and Rx joins that group: and in that setting it can mean treatment or therapy rather than a written prescription. A note might read Rx with rest and ice, which means the plan was rest and ice, not a medicine.
| Short form | Meaning |
|---|---|
| Rx | Prescription, or treatment |
| Tx | Treatment |
| Dx | Diagnosis |
| Hx | History |
| Sx | Symptoms, or sometimes surgery |
Nearby words settle which sense is meant. A drug name and a Sig line point to a prescription, while a plan written in sentences usually means treatment.
For pharmacy technician and coding students
Pharmacy technician students handle Rx all day, from entering new prescriptions to checking refills. A key skill is reading the Sig shorthand and turning it into clear label directions, without copying abbreviations that patients might misread. Coding and scribe trainees see Rx in notes and should check whether it refers to an actual prescription or a broader plan before recording it.
For the full set of order and label shorthand, the prescription abbreviations hub sorts label and order terms by purpose.
The symbol is described here only in general. Your pharmacist is a good first contact for any question about a prescription you have been given or how to read its label.
Frequently asked questions
What does Rx stand for in medical terms?
Rx stands for prescription. It comes from the Latin recipe, meaning take, which opened handwritten prescriptions.
What does Rx only mean on a package?
It means the medicine can be dispensed only with a valid prescription from a licensed prescriber. Products without that wording are sold over the counter.
Is Rx the same as Tx?
Not exactly. The first normally points to a written prescription, and Tx is short for treatment. In chart notes, Rx is sometimes used for treatment too, so the context matters.
What does Sig mean after Rx?
Sig is short for the Latin signa, meaning write or label. It introduces the directions the pharmacist prints on the label.