A 54-year-old woman was admitted to our hospital because of an asthmatic attack. Her first asthma attack occurred when she was 53 years old. It was followed by a flu-like infection, and was preceded for one year perennial rhinitis and loss of the sense of smell. Symptoms were perennial, and unrelated to the seasons. Because these clinical findings resembled those of aspirin-induced asthma (AIA), an aspirin-DL-lysine i.v. challenge test was done. Cough, perspiration, and flushing was provoked within 15 min after aspirin-DL-lysine injection, but FEV1 did not change. Respiratory sounds were normal and no wheezing was audible. Other cyclooxygenase inhibitors (ketoprofen, sulpyrine and acetaminophen) provoked the same symptoms. Successively increasing doses of injected aspirin-DL-lysine resulted in complete tolerance to this stimulus. We propose that aspirin-induced cough without bronchoconstriction is a new type of aspirin hypersensitivity.