Acetaminophen during pregnancy linked to ADHD in kids

Nov. 18, 2017—Many moms-to-be use acetaminophen, a common over-the-counter medicine found in Tylenol and Excedrin. In fact, an estimated 65 to 70% of pregnant women in the United States use it for pain relief. This drug has long been considered safe for use during pregnancy.

But a new study suggests that prenatal exposure to the drug can be trouble. It's linked to higher risk of behavior disorders, such as attention-deficit/hyperactivity disorder (ADHD), in kids.

Acetaminophen and ADHD

The study followed almost 113,000 Danish children and their families, including over 2,246 with ADHD. Researchers sent expecting mothers and fathers surveys at 18 weeks. They also sent follow-up surveys to mothers later during their pregnancy and after delivery. Researchers referenced this info when looking at the children's medical data at age 6 months, 1.5 years, and 3 years.

Almost half of moms reported using acetaminophen while pregnant. The risk of ADHD grew the longer moms used the drug. It was notably stronger if moms took the painkiller into the second and third trimesters of their pregnancies.

When moms used the drug for 29 days or more during pregnancy, their children were twice as likely to be diagnosed with ADHD. Similarly, fathers who used it for 29 days or more before conception were twice as likely to have children with ADHD.

The study also found that the children of women who took the drug to treat fever or infections for 22 to 28 days during pregnancy were six times more likely to be diagnosed with ADHD. Children whose mothers used the drug for less than 8 days had far lower rates of ADHD.

More research needed

Researchers have a few theories as to why this drug might raise a child's risk of ADHD. One theory is that it interferes with hormones related to brain development. But more research is needed.

When researchers discovered that aspirin caused Reye's syndrome, it saved many lives. Confirming this potential cause of ADHD could make a big difference too.

The study was published in Pediatrics.

Safety during pregnancy

During pregnancy, a woman's body changes. Habits that were once healthy might not be the best choice while she’s pregnant.

Expectant mothers should talk to their doctors about any medications and supplements they take. Test your prenatal smarts with our pregnancy quiz.