Anti-inflammatories, non-steroidal


Non-steroidal anti-inflammatory drugs (NSAIDs) are a widely used class of medication that have three main uses:

  • to relieve pain
  • to reduce inflammation
  • to bring down a high temperature (fever)

NSAIDs are available in tablet form and also as a topical treatment (a cream, gel or lotion that is rubbed in to a specific part of the body). Less commonly, NSAIDs are used as a suppository (a capsule that is inserted into the rectum (back passage).

Conditions treated with NSAIDs

NSAIDs are used to treat a wide range of acute (short-term) and chronic (long-term) conditions.

Some common acute conditions that can be treated with NSAIDs include:

  • headaches
  • painful periods
  • infections, such as the common cold or the flu (NSAIDs do not treat the underlying infections but they can help to relieve the symptoms)

Some common chronic conditions that can be treated with NSAIDs include:

  • most types of arthritis, including rheumatoid arthritis or osteoarthritis
  • back pain
  • neck pain

The long-term use of NSAIDs increases your risk of side effects, such as stomach ulcers. Therefore, if you are taking NSAIDs to treat a chronic condition, you may need more treatment to reduce your risk of developing side effects. See NSAIDs - special considerations for more information.

How NSAIDs work

NSAIDs work by interfering with certain enzymes in your body. Enzymes are a special type of protein that help to create, or speed up, a chemical reaction within your body.

NSAIDs interfere with an enzyme called cyclo-oxyganase (COX). Different parts of your body have different types of COX enzymes, which control the production of chemicals called prostaglandins.

Different prostaglandins have different functions.

For example, the stomach contains COX-1 enzymes, which control the production of prostaglandins that help to protect the stomach from acid (which is usually present in the stomach). COX-1 enzymes also keep your blood relatively sticky, which helps to prevent excessive bleeding.

White blood cells contain COX-2 enzymes, which control the prostaglandins that are involved in pain and inflammation. NSAIDs help to reduce pain and inflammation by preventing COX enzymes from releasing the prostaglandin chemicals that cause pain and inflammation.

As NSAIDs block the effects of the COX-1 enzyme on the blood, they can also be used as a blood-thinning medication in people who have a high risk of developing a blood clot.

However, because prostaglandins carry out many different functions within the body, interfering with them can cause a number of different side effects, such as indigestion and stomach ulcers.

Types of NSAIDs

There are two main types of NSAIDs:

  • non-selective NSAIDs – such as ibuprofen, which block the effects of both COX-1 and COX-2 enzymes
  • COX-2 inhibitors – such as celecoxib, which only block the effects of COX-2 enzymes

COX-2 inhibitors were designed to treat chronic conditions that cause pain and inflammation without affecting the stomach.

Although COX-2 inhibitors have less effect on the stomach, they may be more likely to cause side affects on the heart compared with traditional NSAIDs. This means that they may be more suitable for someone who is at risk of developing stomach or intestinal problems, but less suitable for those with a heart or circulation problem.


Some of the most commonly prescribed NSAIDs are:

  • diclofenac
  • ibuprofen
  • naproxen
  • celecoxib
  • mefenamic acid
  • etoricoxib
  • indometacin

Most of the NSAIDs listed above are generic medicines. This means that their production and distribution is not limited to a single company. Therefore, they are available under a range of different brand names.

The exceptions are:

  • celecoxib, which is sold under the brand name Celebrex
  • mefenamic acid, which is sold under the brand name Ponstan
  • etoricoxib, which is sold under the brand name Arcoxia

Two NSAIDs are available over-the-counter (OTC) without the need for a prescription. They are:

  • ibuprofen
  • aspirin


Anti-inflammatory medicines reduce swelling and inflammation.


A fever is when you have a high body temperature (over 38C or 100.4F).


Inflammation is the body's response to infection, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area.


Joints are the connection point between two bones that allow movement.


A migraine is type of recurring headache. It is usually accompanied by nausea, vomiting and sensitivity to light and sound.

Pain is an unpleasant physical or emotional feeling that your body produces as a warning sign that it has been damaged.

Last updated: 13 June 2012

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