Prescription Label Terms

What It Is

When a pharmacy fills a prescription, it prints a label for the container. Laws and regulations require certain information on the label, and pharmacies may add more to help people use medicines safely.

Prescription labels often come with additional printed materials, such as patient information leaflets or, for some medicines, an FDA-required Medication Guide.

This guide explains general label terms only. It does not explain how any individual should take a medicine; that comes from the prescriber and pharmacist.

Common Terminology

Rx number

A number the pharmacy assigns to a prescription, used for refills and questions.

Strength

The amount of active ingredient in each unit, such as each tablet, capsule, or a set volume of liquid.

Directions (Sig)

The instructions from the prescriber about how and when to use the medicine.

Generic name

The official name of the active ingredient. A generic drug contains the same active ingredient as the brand-name version.

Refills

The number of times a prescription can be filled again without a new prescription.

Discard after / use by date

The date after which the pharmacy advises the medicine should not be used. It may differ from the manufacturer's expiration date.

NDC (National Drug Code)

A unique US number that identifies a specific drug product, strength, and package.

Auxiliary label

An extra colored sticker with a warning or tip, such as "may cause drowsiness" or "take with food".

Where You May See These Terms

These terms commonly appear on:

• Pill bottles and other medicine containers from a pharmacy.
• Pharmacy receipts and printed information sheets.
• Mail-order pharmacy packaging.
• Medication lists in patient portals and after-visit summaries.
• Hospital discharge paperwork listing medicines.

Key Concepts

Key parts of a typical prescription label:

• Patient name, which helps make sure the medicine goes to the right person.
• Medicine name (brand or generic), strength, and dosage form, such as tablet, capsule, or liquid.
• Directions for use as written by the prescriber.
• Quantity dispensed, number of refills remaining, and sometimes a date by which refills must be used.
• Prescriber name, pharmacy name, address, and phone number, and the date filled.
• On many labels, a description of what the medicine looks like, such as color, shape, and imprint.

Examples

General examples of wording and abbreviations that may appear:

• "By mouth" or "PO" describes how a medicine is taken; "apply topically" refers to the skin.
• "As needed" or "PRN" means the medicine is used only in situations the prescriber described.
• "Do not crush or chew" often appears on extended-release or specially coated medicines.
• "Shake well" commonly appears on liquid suspensions.
• "Generic for [brand name]" shows that a generic product was dispensed in place of a brand-name product.
• "No refills - contact prescriber" means a new prescription is needed for more medicine.

Tips for Reading

General tips for reading a prescription label:

• Check that the name on the label is correct each time a prescription is picked up.
• Compare the medicine name and appearance with previous fills; pharmacists can explain changes, such as a different generic manufacturer.
• Read auxiliary stickers and any printed leaflets that come with the medicine.
• Note storage instructions, such as "refrigerate" or "keep away from heat and moisture".
• Keep medicines in their labeled containers so the information stays with them.

Getting Clarification

Getting help with label questions:

• Pharmacists can explain directions, abbreviations, warnings, and storage instructions.
• The prescriber can explain why a medicine was prescribed.
• Pharmacies can often print labels in larger type or other languages on request.
• Questions about side effects or using medicines together are generally directed to a pharmacist or prescriber.

Questions to Ask a Healthcare Professional

General questions people often find useful to bring to an appointment:

• Can the directions on this label be explained in plain language?
• What do the warning stickers on this container mean?
• Why does this medicine look different from my last refill?
• How should this medicine be stored?
• How many refills are left, and when do they expire?
• Is a larger-print or translated label available?

Sources

This guide was written in plain language from the following authoritative references.

1. Drugs, Herbs and Supplements — MedlinePlus (U.S. National Library of Medicine)
2. Medicines — MedlinePlus (U.S. National Library of Medicine)
3. Abbreviations — MedlinePlus (U.S. National Library of Medicine)

Related Guides

• Medical TermsCommon Medical AbbreviationsA plain-English guide to common medical abbreviations seen in visit notes, lab reports, prescriptions, and hospital records, such as BP, CBC, and PRN.
• Medical TermsHow Medical Records Are StructuredGeneral guide to the common parts of medical records, such as visit notes, SOAP notes, problem lists, medication lists, results, and discharge summaries.
• Medical TermsHow to Read a Lab Report (General Guide)General guide to the parts of a lab report: test names, results, units, reference ranges, and H/L flags, and why results are interpreted by a clinician.