Aspirin sensitivity and allergy.

Aspirin sensitivity is divided into 2 main subgroups: the bronchospastic and the urticaria/angioedema type. The bronchospastic type of aspirin sensitivity is frequently associated with nonallergic asthma and nasal polyps, producing a classical triad. Nonsteroid anti-inflammatory drugs (NSAID) crossreact with aspirin in aspirin-sensitive patients. Desensitization to aspirin is possible, but should be carried out with caution in selected patients. Desensitization to aspirin also produces desensitization to NSAID. Acetaminophen and nonacetylated salicylic acid (neither are considered NSAID) cross-react with aspirin in a small number of aspirin-sensitive individuals, usually when large doses are administered. The pathogenic mechanism may involve arachidonic acid and prostaglandin metabolism in the bronchospastic type of aspirin sensitivity.