The conventional medical wisdom is that Tylenol (acetaminophen/paracetamol) — the second largest selling analgesic in the United States in dollar terms — is safe in pregnancy at all stages at the recommended doses for short-term use. But disturbing new study asserts that taking Tylenol during pregnancy might double the risk of autism in a child.

This latest blow at the "safety" of acetaminophen as a safe drug for pain adds to mounting evidence that this over-the-counter drug "is actually one of the more dangerous drugs you can get your hands on," according to an analysis by Dr. Joseph Mercola on his medical website.

It's known acetaminophen is the leading cause of acute liver failure in the U.S. Statistics showed that in 2013, lawsuits against Tylenol's side effects had risen dramatically. These lawsuits cited 50,000 trips to the emergency room every year, all due to Tylenol causing liver and kidney failure.

Data released in 2006 showed acetaminophen accounted for some 56,000 emergency room visits and 26,000 hospitalizations annually. The average annual death toll from acetaminophen overdose was 458 persons.

Some sources said that as early as 2005, scientists already knew that “severe acetaminophen hepatotoxicity leads to acute liver failure.” Reports also showed unintentional overdoses of Tylenol accounted for hundreds of suicide attempts, deaths and liver transplants.

A number of studies have also linked acetaminophen use during pregnancy to lifelong repercussions for the child. The drug's use increased a child's risk of developing conduct disorders, hyperactivity and autism.

“Research data suggest that acetaminophen is a hormone disruptor, and abnormal hormonal exposures in pregnancy may influence fetal brain development," according to a 2014 study in the journal JAMA Pediatrics.

Dr. Mercola said this is a significant concern since many pregnant women are likely to use an OTC pain reliever like Tylenol at some point during their pregnancy. The same 2014 study said the use of acetaminophen during pregnancy is associated with a 37 percent increased risk of a child being diagnosed with hyperkinetic disorder, a severe form of attention deficit hyperactivity disorder (ADHD).

These children were also 29 percent more likely to be prescribed ADHD medication by the time they were 7 years old. The strongest associations were observed among mothers that used acetaminophen in more than a single trimester. Therefore, the greater the frequency of use, the more likely their child was to experience behavioral problems.

“Acetaminophen can cross the placenta, making its way to the fetus and its delicate developing nervous system. The drug is a known endocrine (hormone) disrupter, and has previously been linked to undescended testes in male infants," according to one article about the drug.

The same study also said it's "possible that acetaminophen may interrupt brain development by interfering with maternal hormones or via neurotoxicity such as the induction of oxidative stress that can cause neuronal death."

Dr. Mercola added similar findings were published in a 2016 study published in JAMA Pediatrics. The study found use of acetaminophen at 18 and 32 weeks of pregnancy was associated with a 42 percent higher risk of conduct problems and a 31 percent higher risk of hyperactivity symptoms in the child.

When the mother used acetaminophen at 32 weeks of pregnancy, the child also had a 29 percent higher risk of having emotional problems and a 46 percent higher risk of “total difficulties.”

What are some of the health risks of acetaminophen? Scott Olson/Getty Images