celecoxib
Celecoxib (Celebrex) is an oral COX-2 selective nonsteroidal anti-inflammatory drug (NSAID) used for osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, acute pain, and primary dysmenorrhea. It blocks the COX-2 enzyme that makes pain-causing prostaglandins, while largely sparing the COX-1 enzyme that protects the stomach lining. It is taken by mouth in adults and children aged 2 years and older for certain indications.
This page is based on FDA prescribing information for celecoxib capsules, cross-checked with MedlinePlus and the National Cancer Institute drug dictionary; the mechanism is explained in plain language, and analogies are used only where they stay accurate.
How it works
Explains what the medicine does in the body, not dosing, side effects, or safety.
An analogy
When you get a cut, your body sends out chemical 'fire trucks' to the injury site. One of those trucks is made by a machine called COX-2. Celecoxib acts like a parking boot on that specific machine, so fewer fire trucks are produced and the pain and swelling settle down. Because it targets COX-2 and not the related COX-1 machine that protects your stomach, it is gentler on the stomach lining than older NSAIDs.
In simple terms
Celecoxib belongs to a group of medicines called NSAIDs. It works by blocking an enzyme called COX-2. When tissues are injured or inflamed, COX-2 helps the body make chemicals called prostaglandins that cause pain, swelling, and fever. By reducing the amount of these chemicals, celecoxib eases pain and inflammation. Unlike older NSAIDs such as ibuprofen, celecoxib mostly blocks COX-2 and has less effect on COX-1, the enzyme that helps protect the stomach lining. Celecoxib is taken by mouth for conditions including osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, acute pain, and menstrual cramps.
In depth
Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor within the nonsteroidal anti-inflammatory drug class. It competitively inhibits the COX-2 isoform of prostaglandin endoperoxide synthase, reducing the conversion of arachidonic acid to prostaglandin H2 and downstream prostanoids (including PGE2) that mediate inflammation, pain, and fever. At therapeutic doses celecoxib has minimal inhibitory effect on COX-1, thereby preserving COX-1-dependent gastroprotective prostaglandin synthesis and platelet thromboxane A2 production. Celecoxib is indicated for osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis in patients aged 2 years and older, ankylosing spondylitis, acute pain, and primary dysmenorrhea.
See it in motion
A schematic animation of the mechanism — simplified for clarity, not drawn to scale.
How celecoxib blocks the COX-2 machine
- When you get a cut, your body sends out chemical 'fire trucks' to the injury site. One of those trucks is made by a machine called COX-2.
- When tissues are injured or inflamed, COX-2 helps the body make chemicals called prostaglandins that cause pain, swelling, and fever.
- Celecoxib acts like a parking boot on that specific machine, so fewer fire trucks are produced and the pain and swelling settle down.
- Because it targets COX-2 and not the related COX-1 machine that protects your stomach, it is gentler on the stomach lining than older NSAIDs.
Target: Cyclooxygenase-2 (COX-2)
Celecoxib selectively inhibits cyclooxygenase-2 (COX-2), the enzyme responsible for converting arachidonic acid into prostanoids that mediate pain, fever, and inflammation at sites of tissue injury.
Approved uses
Approved uses differ by country and change over time. Always follow your local prescribing information.
Approved uses in United States
FDA- Management of the signs and symptoms of osteoarthritis
- Management of the signs and symptoms of rheumatoid arthritis
- Management of the signs and symptoms of juvenile rheumatoid arthritis in patients 2 years and older
- Management of the signs and symptoms of ankylosing spondylitis
- Management of acute pain in adults
- Management of primary dysmenorrhea
Approved uses in United States
MedlinePlus- Relief of pain, tenderness, swelling, and stiffness caused by osteoarthritis and rheumatoid arthritis
- Treatment of ankylosing spondylitis
- Treatment of juvenile rheumatoid arthritis in children 2 years of age and older
- Treatment of painful menstrual periods and other short-term pain
Official sources
The statements on this page trace back to these records.
- U.S. Food and Drug Administration: celecoxib prescribing information
U.S. Food and Drug Administration
- MedlinePlus: celecoxib
MedlinePlus, U.S. National Library of Medicine
- National Cancer Institute: celecoxib
National Cancer Institute
This page explains how the medicine works — it isn’t the patient leaflet. For anything that applies to you, read the leaflet that came with your medicine or ask your pharmacist.
MedUnfold provides educational content and is not medical advice. Always follow your local prescribing information and healthcare professional.