The study by Express Scripts examined antidepressant use among approximately two million commercially-insured, pediatric beneficiaries 18 years and younger from 1998 to 2002. The fastest growing segment of users were found to be preschoolers aged 0-5 years, with use among girls doubling and use among boys growing by 64%.

For the entire sample, antidepressant use increased from 1.6% in 1998 to 2.4% in 2002, a 49% increase. Over the course of the study, the growth in use was greater among girls (68%) than boys (34%) and, for each gender respectively, growth was higher among younger boys and older girls.

"A number of factors acting together or independently may have led to escalated use of antidepressants among children and adolescents," said Tom Delate, Ph.D., Director of Research at Express Scripts. "These factors include increasing rates of depression in successive age groups, a growing awareness of and screening for depression by pediatricians and assumptions that the effectiveness experienced by adults using antidepressant medications will translate to children and adolescents."

Throughout the five-year period of the study, selective serotonin reuptake inhibitors (SSRI's) were the most commonly dispensed antidepressants, while tetracyclics were the least. SSRI's include paroxetine (also known as Paxil(R)), Prozac(R) and Zoloft(R). Use of paroxetine increased 113% and 91% in females and males, respectively, over the study period. The U.S. Food and Drug Administration (FDA) has recommended that paroxetine not be used in children and adolescents because, among youths, its efficacy has not been established for depression and its use is associated with increased risk of suicidal thinking and suicide attempts. Of the SSRIs, only Prozac has been approved by the FDA for treating depression in children and adolescents.

"There are two differing but not mutually exclusive viewpoints on the increased use of antidepressants in children and adolescents," said Delate. "One is the concern that antidepressants are being prescribed to youths without adequate information about their safety and efficacy in this population. The second is the presumption that advocacy work to identify and treat depression among children and adolescents has begun to pay off. We realize that the use of antidepressants among youths is a critical issue that requires additional research to better understand."

For more than a decade, Express Scripts has employed a company-paid research staff, which now numbers fifteen professionals, three of whom hold PhDs. Many of the studies they conduct are published in peer-reviewed journals, reported in the national media and presented at scientific or professional conferences, including the annual Express Scripts Outcomes Conference held for clients. First published in 1996, the annual Express Scripts Drug Trend Report quickly earned national recognition as the most comprehensive, publicly available analysis of U.S. drug-cost trends. Express Scripts also conducted the first national study of regional variation in prescription-drug utilization patterns across the United States. More information about these and other studies are available at http://www.express-scripts.com/other/news_views/outcomes_research.htm.

Express Scripts, Inc. (Nasdaq:ESRX) is one of the largest pharmacy benefit management (PBM) companies in North America, providing PBM services to over 50 million members through facilities in 13 states and Canada. Express Scripts serves thousands of client groups, including managed care organizations, insurance carriers, third-party administrators, employers and union-sponsored benefit plans.

Express Scripts provides integrated PBM services, including network pharmacy claims processing, mail pharmacy services, benefit design consultation, drug utilization review, formulary management, disease management, medical and drug data analysis services, and medical information management services. The Company also provides distribution services for specialty pharmaceuticals through its Specialty Distribution subsidiary. Express Scripts is headquartered in St. Louis, Missouri. More information can be found at http://www.express-scripts.com/, which includes expanded investor information and resources.