Aspirin sensitivity is a condition in which people have strong reactions to aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs). These reactions include asthma attacks, symptoms that mimic those of an allergic reaction, and gastrointestinal problems.

Aspirin and other NSAIDs are used to reduce inflammation and relieve pain and fever. They do so by inhibiting an enzyme called cyclooxygenase-1 (COX-1). This enzyme is a prime factor in the production of prostaglandins, chemicals that trigger inflammation and pain within the body.

As the drugs inhibit COX-1, they clear the way for other enzymes. In some people, however, this can be harmful. The enzymes can release chemicals that cause inflammation and narrowing of the airways, as well as increased mucus production, triggering an asthma attack.  

Most reactions to aspirin or other NSAIDs fall into two different categories:

• Respiratory reactions such as wheezing, runny nose, shortness of breath
  
  
• Skin reactions such as hives (urticaria) and swelling (angioedema)
  

  

Although the symptoms of aspirin sensitivity may mimic those of an allergic reaction, the condition is not considered a true allergy because the immune system is not involved.

NSAIDs include both prescription and nonprescription drugs such as:

• aspirin (nonprescription)
• ibuprofen (nonprescription)
• naproxen (nonprescription)
• ketoprofen (nonprescription)
• diclofenac (prescription)
• etodolac (prescription)
• fenoprofen (prescription)
• indomethacin (prescription)
• ketoprofen (prescription)
• ketoralac (prescription)
• oxaprozin (prescription)
• nabumetone (prescription)
• sulindac (prescription)
• tolmetin (prescription)

Aspirin sensitivity is most likely to affect those who suffer from both moderate to severe asthma and chronic rhinosinusitis. It is more often found in females and becomes more likely as people age or as their asthma progresses.

Acetaminophen has long been considered a good alternative to NSAIDs for reducing pain or fever. However, recent studies have shown that high doses of this drug can also provoke asthma attacks in some people. In addition, acetaminophen lacks the anti-inflammatory properties of NSAIDs.

A newer class of pain and inflammation medication called COX-2 inhibitors is generally viewed as likely to cause a reaction in patients with aspirin sensitivity. Data released by the U.S. Food and Drug Administration (FDA) shows that some NSAIDs – particularly some types of COX-2 inhibitors – may cause an increased risk of cardiovascular events. Two COX-2 inhibitors, rofecoxib and valdecoxib, have been completely removed from the market. Rofecoxib was found to increase the risk of heart attack and stroke. Valdecoxib was taken off the market because of cardiovascular and gastrointestinal risks. The use of valdecoxib was also found to increase the rate of rare serious skin reactions. Patients should consult their physician when weighing alternatives to aspirin and other NSAIDs.