Infants who have been given the common pain reliever acetaminophen may have a higher risk of developing asthma and eczema by the time they are 6 or 7, a large study covering children in 31 countries has found. One theory is that acetaminophen reduces antioxidants in the body. Some experts think antioxidants, which stop unstable molecules known as free radicals from doing too much damage, can lower the risk of cancer, heart disease, and other ailments. In the United States acetaminophen is widely sold under the brand Tylenol and is used to relieve fever, minor aches and pain.

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