Aspirin to other NSAIDs but also suppresses the normal functioning of platelets. One common adverse effect is an upset stomach. More significant side effects include stomach ulcers, stomach bleeding, and worsening asthma. Bleeding risk is greater among those who are older, drink alcohol, take other NSAIDs, or are on other blood thinners. Aspirin is not recommended in the last part of pregnancy. It is not generally recommended in children with infections because of the risk of Reye syndrome. High doses may result in ringing in the ears. A precursor to aspirin found in leaves from the willow tree has been used
History of aspirin became available without prescription. Also in the early 1980s, several studies suggested a link between children's consumption of aspirin and Reye's syndrome, a potentially fatal disease. By 1986, the U.S. Food and Drug Administration required warning labels on all aspirin, further suppressing sales. The makers of "Tylenol" also filed a lawsuit against "Anacin" aspirin maker American Home Products, claiming that the failure to add warning labels before 1986 had unfairly held back "Tylenol" sales, though this suit was eventually dismissed. The mechanism of aspirin's analgesic, anti-inflammatory and antipyretic properties was unknown through the drug's heyday in the early- to mid-twentieth