Before diving into the how it’s important to note that not everyone with asthma will be affected by ibuprofen. WebMD stated about 20% of people with asthma were sensitive to ibuprofen and other NSAIDs. For some reason, the inhibiting of the COX protein causes people living with asthma to have an allergic reaction. This might be due to the overproduction of leukotrienes in those with asthma. The leukotrienes get released, leading to allergic responses, per Healthline.
The response can range from mild to severe (via Medical News Today). Symptoms for people with asthma include skin rash, runny nose, coughing, and hives. More severe reactions include shortness of breath, facial swelling, bronchospasms, and wheezing. The reaction can happen as soon as 30 minutes of taking ibuprofen but can take as long as 24 hours, according to research in Medicine Baltimore.
Additionally, those with asthma, NSAID intolerance, and nasal polyps can have a condition known as aspirin-exacerbated respiratory disease (AERD), which can be life-threatening if NSAIDs are taken. The American Academy of Allergy, Asthma & Immunology noted that about 9% of adults with just asthma and 30% of those with asthma and nasal polyps have AERD. It’s also noted individuals with AERD don’t typically respond to conventional treatments and suffer chronic sinus infections. They can also develop respiratory reactions when they consume alcohol.