Parker Waichman LLP is Investigating Claims Nationwide for Families Harmed by Prenatal Acetaminophen Use Resulting in Neurodevelopmental Disorders.

For decades, Tylenol® (acetaminophen) has been the most trusted over-the-counter pain reliever for pregnant women. Physicians and medical associations have historically recommended acetaminophen as the safest option for managing fevers, headaches, backaches, and other common discomforts of pregnancy. More than half of pregnant women worldwide report using Tylenol during their pregnancies, with some relying on it frequently for extended periods.

However, new scientific evidence has raised serious concerns about the safety of prenatal acetaminophen use. Recent studies have linked exposure in the womb to a greater risk of children being diagnosed with autism spectrum disorder (ASD) or attention-deficit/hyperactivity disorder (ADHD). A groundbreaking 2025 study led by researchers at Mount Sinai and Harvard applied a rigorous methodology to dozens of human studies and concluded that the evidence is consistent with an association between acetaminophen use during pregnancy and an increased incidence of neurodevelopmental disorders.

What Is Tylenol and Why Pregnant Women Rely on It

Tylenol, known generically as acetaminophen and internationally as paracetamol, is one of the most widely used medications in the world. It has been marketed for decades by Johnson & Johnson’s McNeil Consumer Healthcare subsidiary and is also available in countless generic forms. The drug is used to treat fevers and relieve pain from conditions ranging from mild headaches to chronic musculoskeletal discomfort.

During pregnancy, acetaminophen has long been considered the safest available option. Unlike aspirin and nonsteroidal anti-inflammatory drugs such as ibuprofen, acetaminophen has not been associated with birth defects or miscarriage when used as directed. As a result, physicians frequently recommend it to pregnant women for managing fevers, migraines, uterine cramping, muscle soreness, or general back pain caused by the physical demands of pregnancy. Surveys reveal that more than 60 percent of pregnant women take acetaminophen at some point, and nearly one in five reports using it for more than 20 days over the course of pregnancy. The widespread use of this drug highlights the significance of the new evidence suggesting it may affect neurodevelopment.

Autism and ADHD: Understanding the Disorders

Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are among the most common neurodevelopmental disorders affecting children today. Autism is characterized by challenges with communication, social interaction, and repetitive or restrictive patterns of behavior. Because it is a spectrum disorder, symptoms vary in severity. Some children may experience mild social difficulties, while others may require intensive lifelong care. ADHD, on the other hand, is marked by persistent difficulties with attention, impulsivity, and hyperactivity that interfere with a child’s academic and social functioning.

The prevalence of these disorders has been increasing. According to the U.S. Centers for Disease Control and Prevention (CDC), approximately one in every thirty-six children in the United States is now diagnosed with autism by age eight. ADHD is even more common, with millions of children across the country receiving diagnoses. Families raising children with ASD or ADHD face not only emotional challenges but also significant financial burdens. Therapies, specialized educational services, and long-term medical care can cost hundreds of thousands of dollars over a child’s lifetime. Because of these realities, any factor that increases the risk of these conditions has serious consequences for public health and for families nationwide.

Scientific Evidence Linking Tylenol to Autism and ADHD

The most comprehensive evaluation of the evidence to date was published in Environmental Health in 2025. This study, led by researchers at Mount Sinai, Harvard, and collaborating institutions, systematically reviewed 46 human studies using the Navigation Guide methodology, a respected framework designed for evaluating environmental health risks. The researchers found that more than half of the studies showed statistically significant associations between prenatal acetaminophen use and later diagnoses of autism or ADHD.

This study concluded that the overall weight of the evidence supports a consistent association between prenatal acetaminophen use and neurodevelopmental disorders. Mount Sinai’s announcement of the findings emphasized that while causation cannot be declared with certainty, the evidence is strong enough to warrant caution and clinical guidance limiting use.

Other studies have reinforced these concerns. A 2020 study published in JAMA Psychiatry analyzed umbilical cord blood from nearly one thousand mother-infant pairs. Researchers measured acetaminophen biomarkers directly in the blood and compared them with later diagnoses of ADHD and autism. The results showed a clear dose-response relationship: the higher the biomarker levels, the greater the risk of a child being diagnosed with ADHD or autism.

Acetaminophen crosses the placental barrier quickly, reaching fetal circulation within an hour of maternal ingestion. Laboratory and animal studies show that the drug can trigger oxidative stress in the developing brain, interfere with hormone regulation, and even alter gene expression through epigenetic changes. Such mechanisms provide credible pathways by which prenatal exposure could lead to long-term neurodevelopmental effects.

The U.S. Food and Drug Administration has acknowledged these concerns. In 2015, the agency issued a communication highlighting studies that raised the possibility of an association between acetaminophen use during pregnancy and developmental outcomes in children, while noting that further research was needed.

The safest course of action for pregnant women is to use acetaminophen only under medical supervision, at the lowest effective dose, and for the shortest possible time.

Tylenol Autism Lawsuits

As scientific evidence mounted, families across the United States began filing lawsuits against Johnson & Johnson, generic manufacturers, and major retailers such as Walmart, CVS, and Walgreens. These lawsuits alleged that the companies failed to provide adequate warnings about the potential risks of acetaminophen use during pregnancy.

Plaintiffs in these lawsuits argued that the manufacturers knew or should have known of the potential risks, given the growing scientific literature, but failed to update their labels to adequately warn consumers. They contended that proper warnings would have allowed pregnant women and their physicians to make informed decisions about whether to use acetaminophen.

Who Is Eligible to File a Tylenol Autism Lawsuit

Parents who took Tylenol or generic acetaminophen during pregnancy and later had a child diagnosed with autism or ADHD may be eligible to file a lawsuit. Eligibility is not limited to a specific brand of acetaminophen; both brand-name and store-brand products are implicated in the litigation. Because statutes of limitation vary by state, families are encouraged to seek legal advice as soon as possible to ensure their rights are preserved.

Why Families Choose Parker Waichman LLP

Parker Waichman LLP is one of the nation’s leading product liability law firms. With decades of experience representing clients in mass torts, pharmaceutical litigation, and defective drug cases, our attorneys are prepared to stand up to powerful corporations on behalf of families affected by autism and ADHD.

Our firm represents families on a contingency fee basis, which means there are no upfront costs and no legal fees unless we secure compensation on your behalf. We are committed to guiding families through every step of the process, from gathering medical records and expert testimony to representing clients in court.

If you used Tylenol or acetaminophen during pregnancy and your child has been diagnosed with autism or ADHD, your family may be entitled to pursue a claim. Do not wait to protect your rights.

Call Parker Waichman LLP today at 800-968-7529 for a free and confidential consultation. Our attorneys will review your case, answer your questions, and explain the legal options available to your family.

Our Tylenol autism attorneys will review your medical history, collect supporting evidence, and advise your family of your legal options. We are dedicated to helping families pursue justice and obtain the financial resources they need to care for their children.