The number of American children being treated with psychiatric drugs has grown sharply in the past 15 years, tripling from 1987 to 1996 and showing no sign of slowing, researchers said yesterday.

A newly published study, the most comprehensive to date, found that by 1996, more than 6 percent of children were taking drugs such as Prozac, Ritalin and Risperdal, and the researchers said the trajectory continued to rise through 2000.

While the increase may partly reflect better diagnosis of mental illness in children, the authors said they fear that cost-saving techniques by insurance companies, marketing by the pharmaceutical industry and increased demands on parents and doctors may be driving the increase.

"There are fewer options other than medication," said Michael Jellinek, chief of child psychiatry at Massachusetts General Hospital, who reviewed the new study.

Insurers have increased their profits by decreasing the use of psychotherapy, which is more expensive than drugs in the short run, he said. "The insurance system gave an incentive for medications and a disincentive for therapy."

The insurance industry disputes that interpretation, suggesting instead that more children are getting drugs because more effective medicines have been developed. Most psychiatrists say that a combination of psychotherapy and medication often provides the best treatment.

The new research found steep increases in the use of most classes of medicines, including antipsychotic drugs. Such powerful medications, normally meant to treat schizophrenia, were increasingly being prescribed to children on Medicaid, said the study's lead author, Julie Zito -- possibly as a way to restrain difficult children.

"Other than zonking you, we don't know that behavioral management by drug control is the way to learn to behave properly," said Zito, a researcher at the University of Maryland in Baltimore. "If we are using drugs to control behavior, that doesn't change the underlying problem if someone doesn't know how to get along with their peers."

Zito's study evaluated 900,000 children on Medicaid in a Midwest state, a mid-Atlantic state and in a private HMO in the Northwest. Zito said the large study made it likely that the data are representative of the nation's population. A re-evaluation of one of the health plans in 2000 found that the increase had continued, she added.

"The medicine may help the symptoms but not address issues of self-esteem, interpersonal relationships and family relationships -- all of which are part of recovery," said Jellinek, who analyzed Zito's study. In obsessive-compulsive disorder, for example, he said, "you can get a lot of benefit from behavioral treatments. If someone is getting medicines for OCD, I would like to see them be given a trial of behavioral therapy to see if that helps them and maybe decrease the medication."

Both Zito's study and Jellinek's analysis were published in the most recent issue of the Archives of Pediatrics and Adolescent Medicine.

Susan Pisano, vice president of communications at the American Association of Health Plans, whose members provide managed care to about 160 million people, said the study did not address the quality of care the children received.

"The research doesn't say, 'There is a greater use of drugs and that's having a deleterious effect on children,' " she said. "It just says there is a greater use of drugs." Pisano said more analysis was needed to answer the quality question.

Zito agreed that her study could not determine whether the trend represented a growing awareness of mental illness or was evidence of over-medication and mistreatment. That is because she tracked medication records, not individual children. Without comprehensive studies that tracked the outcome of medication treatment of children, she and Jellinek said, it was difficult to say whether the children were getting the right treatment.

Noting that children are being medicated at almost the same rate as adults, Zito pointed out that few safety studies of the drugs have been done in children. Pharmaceutical companies largely do studies on adults to get new medicines approved or to show that one drug is superior to another.

Jellinek, who is also a professor of psychiatry at Harvard University, said insurance companies should be required to share data about the number of children getting comprehensive treatment in addition to those getting only medicine. Without such information, policymakers cannot independently evaluate whether the treatment is appropriate, he said.

Pamela Greenberg, executive director of the American Managed Behavioral Healthcare Association, which represents companies that cover mental health services to about 110 million Americans, said criticizing the insurance industry for the trend is wrong.

"I don't believe providers are saying, 'We will just provide a medication because that's going to be the highest profit margin for me,' " she said. Besides raising ethical issues, she said, inadequate treatment could result in a child continuing to be sick. "A sick patient from the economic standpoint still costs you money and could end up in the hospital."

Greenberg said the industry might be willing to make some of its internal information public, so long as it was to a national authority that could properly interpret the data.

David Fassler, a psychiatrist at the University of Vermont at Burlington who has testified on children's mental health issues on Capitol Hill for the American Psychiatric Association, said parents should push for comprehensive evaluations of children who develop psychiatric symptoms.

Such evaluations, he said, may entail several sessions with professionals, reviewing a child's developmental history and school records, analyzing the child's functioning at school and with friends and family, and having mental health professionals spend time with children and families.

"You can't do that evaluation in a 5-10 minute office visit," he said. "The reality of contemporary pediatric practice makes it difficult to devote the time necessary to do a full and comprehensive evaluation."