,Aspirin, Inflammation, and COX-2: Medication Facts and Effects

Updated on March 1, 2020
AliciaC profile image

Linda Crampton is a writer and teacher with a first-class honors degree in biology. She often writes about the scientific basis of disease.

Willow trees contain salicin, which is related to aspirin.
Willow trees contain salicin, which is related to aspirin. | Source

A Useful Medication With Some Drawbacks

When aspirin was first created, it was hailed as a wonder drug for inflammation, pain, and fever. It's still a very useful medication. It has many health benefits and is a staple in many people's medicine cabinets. Some people have moved to a different medication because aspirin has drawbacks as well as advantages, however.

Aspirin relieves inflammation due to its ability to inhibit an enzyme in the body called COX-2. Unfortunately, aspirin also inhibits the COX-1 enzyme. This inhibition can lead to stomach irritation and bleeding problems. Aspirin increases bleeding by decreasing the formation of blood clots. The reduction of blood clots may actually be helpful in people with cardiovascular disease. The medication may also be helpful in reducing the risk of some types of cancer, although this benefit is still being investigated.

A weeping willow tree in the spring
A weeping willow tree in the spring | Source

Salicin in Willow Bark

Aspirin is chemically related to salicin, a chemical found in the inner bark of willow trees and also in some other plants. Willow bark has been used to treat pain and fever since ancient times. Salicin is turned into salicylic acid in our digestive tracts.

In the 1800s, scientists isolated salicin from willow trees. They converted it to salicylic acid, which was used as a medicine. The acid often caused severe stomach pain, however. German chemist Felix Hoffmann worked for the Bayer company and is credited with the creation of aspirin in 1897. He converted salicylic acid into acetylsalicylic acid, also known as ASA or aspirin. Aspirin was found to cause less stomach pain than salicylic acid while still relieving other body pains and fever.

Acetylsalicylic acid was given the name Aspirin, from the A for acetyl and the spirin from Spirea, the genus name for shrubs that are an alternative source of salicylic acid.

— Smithsonian Magazine, via the Science History Institute
Inflammation is a helpful process, provided it's short lived. During inflammation, white blood cells travel to the injured area to fight infection.
Inflammation is a helpful process, provided it's short lived. During inflammation, white blood cells travel to the injured area to fight infection. | Source

Inflammation Facts

Inflammation is a normal body response to injury. When tissue is damaged by an infection, chemicals, physical trauma, heat, or radiation, inflammation begins. Extra blood flows to the injured area. This causes fluid to leak out of the blood vessels and produces heat, redness, swelling, and pain. The blood and fluids contain white blood cells and proteins that destroy infectious organisms, such as bacteria and viruses. Inflammation helps to seal off the injured area from the rest of the body. In addition, damaged cells are destroyed and the repair of injured tissues begins.

Inflammation is uncomfortable but is normally a temporary process. This short-lived inflammatory response is known as acute inflammation. Acute inflammation subsides as pathogens are killed and body tissue is repaired. Unfortunately, acute inflammation in certain parts of the body, such as in the brain, is very dangerous. Inflammation that lasts a long time (chronic inflammation) can also be serious and may lead to a variety of health problems.

Extra blood flows through blood vessels to injured areas during the inflammatory response.
Extra blood flows through blood vessels to injured areas during the inflammatory response. | Source

How Aspirin Reduces Inflammation

There are several versions of the COX (cyclooxygenase) enzyme. The best known forms of the enzyme are COX-1 and COX-2. COX-1 is found in most of our cells. COX-2 is much less common but is found in increased amounts in inflamed areas.

The COX enzymes stimulate the body to make chemicals called prostaglandins. Different prostaglandins produce different effects. Some maintain normal body function, but others cause inflammation, pain, and fever. COX-2 stimulates the production of inflammatory prostaglandins. Aspirin inhibits the manufacture of COX-2, thereby decreasing inflammation.

Aspirin may affect the stomach lining.
Aspirin may affect the stomach lining. | Source

Possible Side Effects of Aspirin Use

Aspirin inhibits the COX-1 enzyme as well as the COX-2 enzyme. COX-1 stimulates the production of prostaglandins that maintain the mucus layer inside the stomach. The mucus protects the stomach lining from being attacked by the hydrochloric acid and digestive enzymes that are present in the cavity of the stomach. Without enough mucus in the stomach, a person taking aspirin may develop an inflamed stomach lining (gastritis) and ulcers (sores) on the lining.

Another function of COX-1 is to stimulate blood platelets to make thromboxane A2. This chemical triggers platelets to stick together around a wound, starting the clotting process. Since aspirin inhibits the production of COX-1, it also inhibits blood clotting. Wounds on the stomach lining and elsewhere may bleed more freely during treatment with aspirin.

Aspirin may have other effects in the body. It can cause kidney problems, since COX-1 is needed for normal kidney function. In addition, up to twenty percent of adults with asthma experience an asthma attack when they take aspirin. Aspirin can also cause tinnitus (ringing or other sounds in the ears in the absence of external sounds) or make existing tinnitus worse. In children with a viral disease, aspirin use may cause Reye’s syndrome, a very dangerous condition in which the brain and liver swell.

Aspirin may help to keep the heart healthy.
Aspirin may help to keep the heart healthy. | Source

Aspirin and Cardiovascular Problems

Aspirin’s ability to reduce blood clotting can be a harmful side effect of the medication. It may be a helpful feature in some people, however. These include people at risk for developing blood clots in the heart, a condition that may cause a heart attack, or blood clots in the carotid arteries traveling up the neck to the brain, which could lead to a stroke. Some doctors recommend that patients who have an increased likelihood of developing these disorders take a low dose of aspirin every day.

Some people with peripheral artery disease, or PAD, take aspirin to help their disorder. PAD usually affects arteries travelling to the legs. It's a condition in which an artery is narrowed by fatty deposits on the arterial lining. The narrowed passageway for blood flow increases the chance of blood clot formation.

If you are at risk for developing a cardiovascular problem, talk to your doctor about the advisability of taking aspirin and about a suitable dose. Don't take the medication without your doctor's advice.

Effect of Aspirin on Cancer Risk

Aspirin may have another possible benefit that might be related to its ability to decrease inflammation. The medication may reduce the risk of some types of cancer, especially colorectal cancer. The picture is far from clear, however. In addition, as the video below points out, we shouldn’t expect aspirin to protect us from getting cancer if we perform activities known to promote the disease, such as smoking.

In March 2015, the Fred Hutchinson Cancer Research Center published their analysis of ten large population studies. They concluded that regular aspirin intake is protective against colorectal cancer in most people. However, 9% of the people in their study who had a particular genetic makeup received no benefit from taking aspirin with respect to cancer risk. In 4% of the people with another type of genetic makeup, aspirin actually increased the risk of colorectal cancer. The center concludes that more research is needed and that they can't yet make a blanket recommendation that we all take aspirin to prevent cancer.

It will be interesting to see if researchers discover how aspirin works to protect people from cancer (if in fact it does) and whether this protection results from its ability to reduce inflammation, as has been speculated. There is evidence linking chronic inflammation to cancer development. It will also be interesting to discover why aspirin's action seems to depend on genetics.

The information in this article is given for general interest. All medicines have potential side effects as well as benefits. Anyone who wants to take a particular NSAID (including aspirin) should consult their doctor or pharmacist.

Over-the-Counter NSAIDs

NSAIDs (Nonsteroidal Anti-Inflammatory Drugs) are a group of chemicals that include aspirin. Like aspirin, ibuprofen and naproxen are NSAIDs and inhibit both COX-1 and COX-2. Acetaminophen (paracetamol) is not an NSAID. It's used to treat pain and fever, but it only weakly inhibits the COX-2 enzyme and is not anti-inflammatory. Acetaminophen is believed to exert its effects by acting on the central nervous system.

The medications mentioned in the paragraph above are said to be over-the-counter drugs because they can be bought without a prescription. Doctors can prescribe different NSAIDs that may be more advantageous for a patient's condition.

New drugs have been created that inhibit COX-2 but not COX-1. These drugs don’t create stomach problems since they don’t inhibit the COX-1 enzyme. Unfortunately, some of them have been found to cause serious health problems, including an increased risk of heart attack, stroke, and liver damage, and have been withdrawn from the market.

An Anti-Inflammatory Diet and Inflammation

Over the long-term, an anti-inflammatory diet may help to decrease chronic inflammation and even reduce the need for certain medications. It's very important that you don't reduce the dose of a medication or stop taking it without your doctor's advice, however.

In an anti-inflammatory diet, foods that are believed to reduce inflammation are emphasized while those that are thought to increase it are avoided, or at least limited. In general, vegetables, fruits, legumes (pulses), whole grains, fish, nuts, and seeds are considered to anti-inflammatory, provided they are eaten in an unprocessed form. On the other hand, refined grains, sugar, excess saturated fats, hydrogenated fats, and alcohol are generally thought to increase inflammation.

Chronic inflammation contributes to many health problems. Some of these problems include rheumatoid arthritis, asthma, and inflammatory bowel disease. If you have a disorder that involves inflammation, it’s worth following an anti-inflammatory diet to see if it reduces your symptoms. The diet is considered to be healthy for everyone, whether or not they are experiencing inflammation.

Anyone with specific questions about an anti-inflammatory diet with respect to their life should consult a health professional, such as a nutritionist, dietitian, or physician.

Salmon is a good source of omega-3 fatty acids.
Salmon is a good source of omega-3 fatty acids. | Source

Specific Foods That May Reduce Inflammation

Fats containing omega-3 fatty acids have been shown to reduce inflammation. Oily fish such as wild salmon and sardines are good sources of omega-3 fatty acids known as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Foods such as walnuts and flax seeds contain a different form of omega-3 fatty acid. Our bodies can convert this form into EPA and DHA, although in limited amounts.

Extra virgin olive oil contains oleocanthal, which can produce a stinging sensation in the throat like ibuprofen sometimes does. It also appears to lower the levels of COX-1 and COX-2 like ibuprofen, reducing inflammation. The amount of olive oil that is normally ingested each day is equivalent to a weak dose of ibuprofen, but it’s thought that over time the regular consumption of extra virgin olive oil can decrease inflammation. Other substances that are believed to reduce inflammation are green vegetables, berries, herbs, and certain spices, especially ginger and turmeric.

Berries are an important component of an anti-inflammatory diet.
Berries are an important component of an anti-inflammatory diet. | Source

Taking Aspirin

Don't start taking daily aspirin (or a different NSAID) for any reason without consulting your doctor. Some people experience unpleasant and potentially dangerous side effects from aspirin use. People with certain medical conditions shouldn't take the medication. In addition, certain drugs shouldn't be combined with aspirin. The dose that's taken is also an important point to consider.

It's very interesting that such an old medication as aspirin still has important uses, despite the creation of newer drugs. It's not ideal for everyone and is associated with problems as well as benefits, but for some people it's a very helpful medicine.


This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

© 2011 Linda Crampton


    0 of 8192 characters used
    Post Comment
    • AliciaC profile imageAUTHOR

      Linda Crampton 

      8 years ago from British Columbia, Canada

      Yes, I eat omega-3 fish, avocados and olive oil too, BlissfulWriter. I don't take omega-3 supplements because I prefer to get my good fats from food. Supplements would be good in some situations, though. Thank you very much for the visit and the comment.

    • BlissfulWriter profile image


      8 years ago

      We must have a some amount good fats everyday to keep inflammation down. I like to get them from avocados, sardines, salmon, and olives. I also take omega-3 and krill-oil supplements.

    • AliciaC profile imageAUTHOR

      Linda Crampton 

      8 years ago from British Columbia, Canada

      Thank you for the visit and the comment, Moon Willow Lake.

    • Moon Willow Lake profile image

      Moon Willow Lake 

      8 years ago

      Thank-you for this detailed information, and for describing the willow tree's part in all this.

    • AliciaC profile imageAUTHOR

      Linda Crampton 

      9 years ago from British Columbia, Canada

      Hi, breakfastpop. Thank you for your comment. You're right - aspirin is very helpful but must be used carefully.

    • breakfastpop profile image


      9 years ago

      Very informative hub. Aspirin is a miracle drug that is so often taken for granted. Of course, like anything else it must be taken properly.

    • AliciaC profile imageAUTHOR

      Linda Crampton 

      9 years ago from British Columbia, Canada

      Hi, Martie. Thanks for commenting. It’s scary how a medicine that can be so helpful can sometimes be so dangerous. Reye’s syndrome is considered to be a rare disease, but it's potentially fatal.

    • MartieCoetser profile image

      Martie Coetser 

      9 years ago from South Africa

      When my children were small the dangers of Aspirin were not known, and I’ve broken their fevers – in particular caused by tonsilitis – within minutes with only half of an aspro. Now I shudder when I read about the dangers. Thank heavens my children survived that. Thanks, Alicia, for this informative and excellent hub about Aspirin.

    • AliciaC profile imageAUTHOR

      Linda Crampton 

      9 years ago from British Columbia, Canada

      Hi, kashmir56. Thanks for your comment. I enjoy researching how medications work in the body.

    • kashmir56 profile image

      Thomas Silvia 

      9 years ago from Massachusetts

      Hi AliciaC thank you for this great and well researched hub on aspirin . Some of it i did not know.


    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, youmemindbody.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://maven.io/company/pages/privacy

    Show Details
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)
    ClickscoThis is a data management platform studying reader behavior (Privacy Policy)