How is aspirin-induced asthma diagnosed?
The diagnosis can be made on history alone, if the patient has a history of
asthma or rhinitis triggered within 1-3 hours of taking aspirin or NSAIDs.
However, some patients with this condition may never have taken aspirin or
NSAIDs. The clinical features of late-onset asthma, and prominent rhinitis with
nasal polyposis increase the index of suspicion for AIA.
If the patient is already on regular aspirin or NSAIDs, the diagnosis of AIA
is very unlikely, and the medication should not be stopped. Any suspicion of
aspirin-induced asthma should be referred to an allergy specialist or
respiratory physician for further assessment.
There are no blood tests or skin tests that will diagnose allergy to aspirin
or NSAIDs. Confirmation of the diagnosis, if appropriate, requires controlled
challenge with aspirin. This should only be done in a specialist clinic with
appropriate resuscitation facilities.
How is aspirin-induced asthma treated?
In general, aspirin-induced asthma is managed in the same way as other types
of asthma. Some patients with this condition may benefit from the addition of
leukotriene receptor antagonist medication such as montelukast, but the response
is variable and needs to be judged on an individual basis.
Desensitisation to aspirin is possible by graded introduction of aspirin and
staying on a daily maintenance dose. In some patients, desensitisation improves
nasal symptoms and asthma control and reduces the recurrence of nasal polyps.
Desensitisation is also indicated if the patient requires aspirin or NSAIDs for
cardiovascular prophylaxis or the treatment of arthritis. This should only be
done under the supervision of a specialist with experience of the procedure.7
<LE III-3>
What pain relievers can patients with aspirin-induced
asthma take?
Aspirin and NSAIDs are safe for the majority of people with asthma.
Obviously, these medications should be avoided in patients with a positive
diagnosis of aspirin-induced asthma, or where there is suspicion of the
diagnosis.
Paracetamol is generally safe for patients with diagnosed or suspected
aspirin-induced asthma. At high doses (more than 1000-1500mg per dose),
paracetamol should be used with caution, as it can inhibit cycloxygenase and
cause mild asthma symptoms in some patients sensitive to aspirin.8
<LE III-2>
While the newer COX-2 inhibitors (selective NSAIDs), such as celecoxib, have
been used safely in patients with aspirin-induced asthma, occasional cases of
anaphylaxis and drug-induced asthma have been reported.9,10
<LE III-1> However,
as these medications are new to the market and may not be 100% selective to
COX-2, caution is still advised when prescribing them for patients with a
history of aspirin-induced asthma, especially at high doses.
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