An international study which looked at data on 205,487 children in 31 countries has raised concerns about the potential risk of developing asthma in babies who are given acetaminophen (paracetamol, Tylenol, Panadol). Other irritations such as eczema and having a runny nose and itchy eyes may also be related to acetaminophen use.

The study highlights the need of randomized controlled trials to determine whether these findings can be proven in a controlled environment. The figures are worrying, as children who took paracetamol had: a 46% increased risk of asthma at ages 6-7 years; a 48% increased risk of runny nose and red, itchy eyes; a 35% increased risk of eczema.

The study also may help explain why asthma cases skyrocketed. They apparently went up about the same time when paracetamol use became widespread.

Paracetamol or acetaminophen is an analgesic and antipyretic chemical derived from coal tar. Because it is well-tolerated and lacks many of the side-effects of non-steroidal anti-inflammatory drugs (NSAIDs), it became widespread since its introduction in the 1950s. It is safe during pregnancy but it is known to cause liver damage in large doses. Thus paracetamol toxicity is the most common cause of acute liver failure in both the United States and the United Kingdom.