The finding, published on Aug. 29 in JAMA Network Open, highlights a gap in medical care for 4- and 5-year-olds with ADHD. Treatment guidelines recommend that these young children and their families try six months of behavior therapy before starting ADHD medication.

But pediatricians often prescribe medication immediately upon diagnosis, according to an analysis of medical records from nearly 10,000 young children with ADHD who received care in eight pediatric health networks in the United States.

"We found that many young children are being prescribed medications very soon after their diagnosis of ADHD is documented," said the study's lead author, Yair Bannett, MD, assistant professor of pediatrics. "That's concerning, because we know starting ADHD treatment with a behavioral approach is beneficial; it has a big positive effect on the child as well as on the family."

In addition, stimulant medications prescribed for the condition cause more side effects in young patients than they do in older children, Bannett said. Before age 6, children's bodies don't fully metabolize the drugs.

"We don't have concerns about the toxicity of the medications for 4- and 5-year-olds, but we do know that there is a high likelihood of treatment failure, because many families decide the side effects outweigh the benefits," he said. Stimulant medication can make young children more irritable, emotional and aggressive.

ADHD is a developmental disorder characterized by hyperactivity, difficulty paying attention and impulsive behavior.

"It's important to catch it early because we know these kids are at higher risk for having academic problems and not completing school," Bannett said. Early identification and effective treatment for ADHD improve children's academic performance. Research has shown that good treatment also helps prepare individuals with ADHD for many aspects of adulthood, such as maintaining employment, having successful relationships and avoiding trouble with the law.

Complementary treatments

Behavioral therapy and medication, the two mainstays of ADHD treatment, have different purposes.

"Behavioral treatment works on the child's surroundings: the parents' actions and the routine the child has," Bannett said. The therapy helps parents and kids build skills and establish habits compatible with how the child's brain works.

The evidence-based behavioral treatment recommended by the American Academy of Pediatrics is called parent training in behavior management. The training helps parents build strong, positive relationships with their children; offers guidance in rewarding a child's good behaviors and ignoring negative behaviors; and recommends tools that help kids with ADHD, such as making visual schedules to help them stay organized.

In contrast, medication relieves ADHD symptoms such as hyperactivity and inattentiveness, with effects that wear off as the body breaks down each dose of the drug.

Both approaches are needed for most kids with ADHD to do well. But previous studies of preschoolers diagnosed at age 4 or 5 show that it's best to start with six months of behavioral treatment before prescribing any medication.

Rapid prescriptions

The researchers analyzed data from electronic health records for children seen at primary care practices affiliated with eight U.S. academic medical centers. They began with 712,478 records from children who were 3, 4 or 5 years old and were seen by their primary care physician at least twice, over a period of at least six months, between 2016 and 2023.

From these records, the scientists identified 9,708 children who received an ADHD diagnosis, representing 1.4% of the children in the initial sample. They found that 42.2% of these children -- more than 4,000 kids -- were prescribed medication within a month of their ADHD diagnosis. Only 14.1% of children with ADHD first received medication more than six months after diagnosis. The researchers did not have access to data on referrals to behavioral therapy, but since young children are supposed to try the therapy alone for six months before receiving medication, any who were prescribed medication sooner were likely not being treated according to academy guidelines. A smaller study of recommendations for behavior therapy, published in 2021, found only 11% of families got the therapy in line with guidelines.

Children who were initially given a formal diagnosis of ADHD were more likely to get medication within the first 30 days than those whose medical charts initially noted some ADHD symptoms, with a diagnosis at a later time. But even among preschoolers who did not initially meet full criteria for the condition, 22.9% received medication within 30 days.

Barriers to behavioral treatment?

Because the study was based on an analysis of electronic medical records, the researchers could not ask why physicians made the treatment decisions they did. However, Bannett's team had informal conversations with physicians, outside the scope of the study, in which they asked why they prescribed medication.

"One important point that always comes up is access to behavioral treatment," Bannett said. Some locales have few or no therapists who offer the treatment, or patients' insurance may not cover it. "Doctors tell us, 'We don't have anywhere to send these families for behavioral management training, so, weighing the benefits and risks, we think it's better to give medication than not to offer any treatment at all.'"

Bannett said he hopes to educate primary care pediatricians on how to bridge this gap. For example, free or low-cost online resources are available for parents who want to learn principles of the behavioral approach.

And while the study focused on the youngest ADHD patients, behavioral management therapy also helps older children with the diagnosis.

"For kids 6 and above, the recommendation is both treatments, because behavioral therapy teaches the child and family long-term skills that will help them in life," Bannett said. "Medication will not do that, so we never think of medication as the only solution for ADHD."

Researchers contributed to the study from the Children's Hospital of Philadelphia, the Perelman School of Medicine at the University of Pennsylvania, Nationwide Children's Hospital, The Ohio State University College of Medicine, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Texas Children's Hospital, Baylor College of Medicine, Ann and Robert H. Lurie Children's Hospital of Chicago, Children's Hospital of Philadelphia, the University of Colorado, and Nemours Children's Hospital. `

This work was supported by the Stanford Medicine Maternal and Child Health Research Institute; the National Institute of Mental Health (grant K23MH128455); and the National Heart, Lung, and Blood Institute (grant K23HL157615). The study was conducted using PEDSnet, A Pediatric Clinical Research Network. PEDSnet was developed with funding from the Patient-Centered Outcomes Research Institute.

The study, published in the August 23, 2025 online edition of The Lancet, found that the medication, ION224, targets a liver enzyme called DGAT2, which plays a key role in how the liver produces and stores fat. By blocking this enzyme, the drug helps reduce fat buildup and inflammation, two major drivers of liver damage in MASH.

"This study marks a pivotal advance in the fight against MASH," said Rohit Loomba, MD, principal investigator of the study and chief of the Division of Gastroenterology and Hepatology at UC San Diego School of Medicine. "By blocking DGAT2, we're interrupting the disease process at its root cause, stopping fat accumulation and inflammation right in the liver."

The multicenter, Phase IIb clinical trial involved 160 adults with MASH and early to moderate fibrosis across the United States. Participants received monthly injections of the drug at different doses or a placebo over the course of one year. At the highest dose, 60% showed notable improvements in their liver health compared to the placebo group. These benefits occurred regardless of weight change, suggesting the drug could be used alongside other therapies. The medicine showed no serious side effects linked to the treatment.

MASH, formally known as nonalcoholic steatohepatitis (NASH), affects people with metabolic conditions like obesity and type 2 diabetes. It is often called a "silent" disease because it can progress for years without symptoms.

More than 100 million people have some form of fatty liver disease in the U.S. and as many as 1 in 4 adults worldwide may be affected, according to the Centers for Disease Control and Prevention. If left untreated, MASH can progress to liver failure and often may require a transplant.

"This is the first drug of its kind to show real biological impact in MASH," Loomba said. "If these findings are confirmed in Phase III trials, we may finally be able to offer patients a targeted therapy that halts and potentially reverses liver damage before it progresses to life-threatening stages."

Loomba, who is also director of the metabolic-dysfunction associated steatotic liver disease (MASLD) research center at UC San Diego School of Medicine, and a gastroenterologist and hepatologist at UC San Diego Health, adds that for patients and families affected by this serious condition, these results bring new hope for better care and outcomes. He emphasizes that early intervention and targeted therapies may also help reduce the burden on health care systems by preventing costly and complex liver disease down the line.

Next steps include a larger clinical trial to move closer to making this treatment widely available.

Co-authors of the study include Erin Morgan, Keyvan Yousefi, Dan Li, Richard Geary, Sanjay Bhanot, all from Ionis Pharmaceuticals, and Naim Alkhouri, Arizona Liver Health.

Funding for this research came from Ionis Pharmaceuticals (ION224-CS2).