How Does Indomethacin Work? - MedicineHow

How Does Indomethacin Work?

How Does Indomethacin Work

Indomethacin, also known as Indometacin, is a type of drug called a non-steroidal anti-inflammatory drug (NSAID). It works by stopping the production of compounds called prostaglandins in the body, which have a number of effects such as to cause inflammation.

As a result, indomethacin can help to reduce pain and inflammation by stopping the production of prostaglandins. This is why it is usually used to relieve painful inflammatory conditions, such as arthritis.

Brand Names and Doses

Indomethacin is the generic name of the drug, which is the name of the active component that has an effect on your body. You may also know it better by a brand name, which is the name given to the medication made by each pharmaceutical company so that they can market it.

The brands name of indomethacin are Athrexin and Indocid. Both of these brand are available as capsules containing 25mg of the drug.

Indomethacin is also available as a suppository containing 100mg of the drug, under the brand name Indocid. Using a suppository means that the capsules do not need to be swallowed and there side effects related to the stomach, such as gastrointestinal ulcers or bleeding are less likely to occur. However, many people find suppositories uncomfortable to use.

What type of drug is it?

Indomethacin is a type of drug known as a non-steroidal anti-inflammatory drug (NSAID), which is a group of drugs that all work in a similar way. Other examples of NSAIDs include:

Indomethacin is a nonselective NSAID, which means that it blocks both COX-1 and COX-2 to stop the production of more types of prostaglandins than some other NSAIDs. This means that it is more likely to cause side effects due to the action of the other prostaglandins that are reduced.

What is Indomethacin used for?

Indomethacin can be used to help relieve symptoms of pain and inflammation caused by a variety of health conditions. Your doctor may recommend it for:

  • Rheumatoid arthritis

  • Osteoarthritis

  • Gout

  • Ankylosing spondylitis

  • Period pain

  • Post-surgery pain

  • Muscular injury pain

  • Actinic keratosis

How does it work?

Indomethacin works by inhibiting COX-1 and COX-2, which are needed to produce the different prostaglandins in your body.

You have many different types of prostaglandins in your body, and there are some in almost every tissue of your body. They each have different effects, such as to cause:

  • the tissues in your body to become inflamed

  • your blood vessels to relax and widen

  • the platelets in your blood to come together to form a clot

Indomethacin has a general effect on almost all the prostaglandins because it blocks both COX-1 and COX-2 from producing prostaglandins in your body. This means that it can reduce all of the usual effects prostaglandins. We want it to reduce inflammation because that is why we are using it, but it can also cause hypertension and affect the way the blood forms clots.

Side Effects

There are many different side effects that you may experience if you are taking indomethacin. These do not affect everyone, but it’s important to know what they are so that you can recognize them if you do notice them.

The side effects of Indomethacin may include:

  • ​Vertigo

  • Nausea​

  • Heartburn (dyspepsia)

  • Diarrhea

  • Headache

  • Dizziness

  • Gastrointestinal ulcers

  • Gastrointestinal bleeding

  • Hypertension

It is best to take the capsules with or straight after food because this helps to reduce the risk of side effects.

This is not a complete list of side effects, but just some of the most common. Please see the information leaflet for more detailed information.

Drug Interactions

Indomethacin can interact with many other medications when they are used in together, including:

  • ACE Inhibitors

  • Aldosterone antagonists

  • Alendronate

  • Amiloride

  • Aspirin

  • Beta blockers

  • Brimonidine

  • Calcineurin inhibitors

  • Corticosteroids

  • Cyclosporin

  • Fluconazole

  • Lithium

  • Loop diuretics

  • Methotrexate

  • Phenindione

  • Potassium

  • Prostaglandin analogues

  • Rifampicin

  • Sartans

  • Tacrolimus

  • Thiazide diuretics

  • Thiazolidinediones

  • Triamterene

  • Warfarin

These medications can often be used together, but your doctor should be aware that you are taking both medications so that they can adjust the dose as needed to ensure they are safe and effective.


There are some people who may need to avoid using Indomethacin, or use it with caution, because they may be at risk of side effects due to the medication.

Peptic ulcers or GI bleeding:


Coagulation disorders:

Cardiovascular disease:


Inflammatory Bowel Disease (IBD):

Renal Impairment

Pregnancy and Breastfeeding

Indomethacin is not usually recommended for women who are pregnant or trying to conceive. This is because it can interfere with fertility and the development of the fetus.

For women planning to become pregnant, it can prevent or delay ovulation, so that the woman is less likely to conceive. Additionally, using indomethacin during pregnancy, particularly at the time of conception, is linked to a higher risk of miscarriage. It may also cause other problems later on in the pregnancy and should be avoided.

For women who are breastfeeding, indomethacin is considered safe to use.

Pin it!

How Does Indomethacin Work?
About the author


Yolanda is a passionate medical writer who loves to help people understand how health and different treatments work. After graduating in Pharmacy in Australia, she moved to Italy to study the Mediterranean way of life and continue learning about health and medicine.

Leave a comment: