The science behind ibuprofen

Let’s begin with the basics – how does ibuprofen work? Well, ibuprofen helps relieve pain caused by inflammation, which occurs when the body produces increased amounts of molecules called prostaglandins1,3 when you have an illness or injury.

When prostaglandins are released, they make nearby nerves more sensitive to pain4 – which helps your body realise something is wrong.5 So for example, when you put your hand on something sharp, the nearby nerves tell your brain, which sends a message that your hand hurts.

Prostaglandins also make tissues inflamed and swollen4 – they are one of the reasons why you get a sore throat when you are sick6 and why a sprained ankle becomes swollen and painful.4

What does ibuprofen do to help? It decreases the production of prostaglandins throughout the body,1,7 which means the prostaglandins can’t cause as much inflammation or increase your sensitivity to pain as they usually would. In this way, ibuprofen can be used to help relieve body pain caused by inflammation. This is why ibuprofen belongs to a class of drugs called non-steroidal anti-inflammatory drugs (NSAIDs) – it has anti-inflammatory properties to reduce pain and inflammation.8

What are the different types of ibuprofen available?

Ibuprofen comes in a range of different formulations.1,2 The two most common are oral formulations, which can be swallowed with water,2 and topical formulations, which are applied to the skin.2

After you swallow an ibuprofen tablet or caplet, it ends up in your stomach where it begins to dissolve. As the tablet or caplet dissolves, ibuprofen is released from the tablet or caplet and absorbed into your bloodstream.7 Once ibuprofen is absorbed into the bloodstream, it travels throughout the body, and can start blocking prostaglandins from being made,1 which helps to reduce pain and inflammation.7

As mentioned, there are different brand names of ibuprofen, including Nurofen. If you’re wondering if there’s a difference between ibuprofen vs Nurofen, ibuprofen is the active ingredient in Nurofen.

You may have taken Nurofen previously and found yourself wondering: How long does Nurofen take to work? It depends on the formulation of medication you have taken. In recent years, different formulations of ibuprofen have been developed. Two examples are ibuprofen lysine (Nurofen Quickzorb) and ibuprofen sodium dihydrate (Nurofen Zavance).9 The ibuprofen sodium dihydrate formulation (Nurofen Zavance) is absorbed up to twice as fast as standard Nurofen.9,10

Tablets or caplets are best used for adults and children aged over 12 years. But there are other formulations of ibuprofen that have been specifically designed for pain relief in children. Children’s liquid formulations or soft chewable capsules are available. Children’s liquid ibuprofen can be used from 3 months and the soft chewable capsules can be used from 7 years of age.11

Topical ibuprofen – Topical ibuprofen comes as a gel and is applied directly onto painful parts of the body as directed on the label.12 It is absorbed into the skin at the site of pain.12

What is ibuprofen used for?

At over-the-counter doses, ibuprofen is used to provide temporary relief of mild-to-moderate pain and fever. It can also reduce redness, swelling and soreness associated with inflammation.11,13

Ibuprofen can be used to provide temporary relief of pain and/or inflammation associated with:11,13

  • Headaches (e.g. migraines, tension headaches)
  • Muscle pain (e.g. strains and sprains, sport injuries)
  • Cold and flu symptoms
  • Period pain
  • Back pain
  • Dental pain, including toothache and pain after dental procedures
  • Joint pain (e.g. arthritic pain)
  • Joint and tendon sprains and strains
  • Sinus pain

Ibuprofen vs paracetamol: types of pain relievers

Pain relievers available in your supermarket or pharmacy can be divided into two groups:

  • Those that mainly act at the site of the inflammation
  • Those that are thought to mainly act centrally – in the brain

Ibuprofen, aspirin, and other non-steroidal anti-inflammatory drugs (NSAIDs) work by blocking pain signals mainly at the site of inflammation.4,7

Paracetamol is a different kind of pain reliever that is thought to act mainly in the central nervous system (the brain).14 


  Ibuprofen Paracetamol
Type of medicine Non-steroidal anti-inflammatory drug (NSAID)


How it works

Blocks pain signals mainly at the site of inflammation

Thought to work mainly centrally (via the brain) to reduce intensity of pain signals

Common brand names Nurofen, Advil, Rafen,Herron Blue Panadol, Lemsip Max, Dymadon, Febridol, Herron Gold, Panamax

Panadol is a registered trademark of the GSK group of companies. Advil is a registered trademark of the Haleon group of companies.

History of ibuprofen

In 1953, Dr Stewart Adams, a pharmacist and pharmacologist, and Dr John Nicholson, a chemist, began research for the UK-based Company, Boots. They were working to find an analogue of aspirin that might be suitable for long-term use for a painful inflammatory condition. In 1961 they patented ibuprofen, which was launched in 1969 for the treatment of rheumatic diseases in the UK. In the following years, ibuprofen was approved for the treatment of an increasing number of conditions. Boots sold their ibuprofen product to Reckitt Benckiser in 2005, and research of ibuprofen has continued to the present day.15

What is an NSAID?

NSAIDs (short for non-steroidal anti-inflammatory drugs), also called anti-inflammatories help relieve pain and reduce inflammation.7 As mentioned, prostaglandins are known to increase inflammation and make your body more sensitive to pain.16 NSAIDs work by inhibiting the production of pain-causing chemicals called prostaglandins.1

There are many types of NSAIDs available in both supermarkets and pharmacies.16 Over-the-counter NSAIDs that you can select for yourself include aspirin, diclofenac, naproxen, and ibuprofen.16 Choosing the most appropriate NSAID depends on your individual circumstance and whether you have other/co-existing medical conditions.

Other NSAIDs are available with a prescription from your doctor.17

What are the side effects of ibuprofen?

Ibuprofen may be used to provide short-term relief of pain, fever and inflammation. These may include headaches, period pain, pain associated with cold and flu symptoms and more.

However, as with all medicines, side effects can occur although not everyone will experience them.

Some people may experience the following side effects with ibuprofen:13

Talk to your doctor

If you have pre-existing conditions or are aged over 65 years, there are extra risks with taking ibuprofen as it can make heart, liver, or kidney disease worse – therefore talk to your doctor if you have these conditions. You should also talk to your doctor before taking ibuprofen if you have asthma, are taking low-dose aspirin, and/or if you’re pregnant or breastfeeding.13

If you are experiencing side effects from an ibuprofen-containing medication, speak to your doctor or pharmacist immediately.

Should I take ibuprofen if I have allergies?

Nurofen and Nurofen for Children both contain ibuprofen and are commonly used to relieve pain and reduce fever. If you are allergic to ibuprofen, aspirin or other anti-inflammatory medicines, do not use Nurofen or Nurofen for Children. If you or your child experiences an allergic reaction with Nurofen or Nurofen for Children, stop using it and see your doctor immediately. If you are concerned about any existing allergies you may have that could interfere with your use of ibuprofen, speak to your doctor.

How does ibuprofen affect blood pressure?

If you have concerns about how ibuprofen may affect your blood pressure, please speak to a healthcare professional. If you are taking other medication, you should not use Nurofen unless a doctor has told you to.

Can ibuprofen cause an upset stomach?

Did you know ibuprofen does not need to be taken with food? Taking ibuprofen with food can sometimes delay the time it takes to work.18,19 If you would like to know more about any potential stomach-related side effects associated with ibuprofen you should speak to your doctor or pharmacist.


Ibuprofen provides temporary relief of mild-to-moderate pain and helps to reduce inflammation when taken as directed. It is available in various formulations for both adults and children over 3 months of age. If you are concerned about any side effects with ibuprofen, always speak to a doctor or pharmacist for further advice.

Important information

Some medicines may not be right for you so always read the label before purchase and follow the directions for use. If you use medicines incorrectly, they can harm you. If your symptoms persist, talk to your health professional.

This article is for general information only and not intended as a substitute for medical advice. All information presented on these web pages is not meant to diagnose or prescribe. In all health-related matters, always consult your health professional.

Always read the label and follow the directions for use. Incorrect use could be harmful.





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