The findings, published in the journal Pediatrics, show that although psychiatric diagnoses increased from 2006 to 2009, the use of psychotropic drugs leveled off.
"The likelihood of receiving a behavioral diagnosis increased in 2006 to 2009, but this was not accompanied by an increased propensity toward psychotropic prescription," says senior author Tanya Froehlich, a pediatrician at Cincinnati Children's.
"In fact, the likelihood of psychotropic use in 2006-2009 was half that of the 1994-1997 period among those with a behavioral diagnosis," Froehlich said.
Psychotropic usage decreased from 43 percent of those with one or more behavioral diagnoses in 1994-1997 to 29 percent in 2006-2009.
Commonly prescribed psychotropic medications include stimulants, antipsychotics, antidepressants and anti-anxiety drugs. Though the FDA has approved few medications for children aged 2 to 5, previous studies showed a two- to threefold increase in psychotropic prescriptions in that age group between 1991 and 2001.
Overall use among the preschool set peaked from 2002-2005. Researchers say it's likely that increased warnings about these drugs in the mid-2000s contributed to fewer children with diagnoses using prescription medication.
Researchers also discovered increased use of these medications among boys, white children and those without private health insurance during the 16-year study period, 1994-2009.
Dr. Froehlich says more research is necessary to determine why boys, white children and those without private health insurance are more likely to receive these medications -- and to determine their appropriateness.
"Our findings underscore the need to ensure that doctors of very young children who are diagnosing ADHD, the most common diagnosis, and prescribing stimulants, the most common psychotropic medications, are using the most up-to-date and stringent diagnostic criteria and clinical practice guidelines," Froehlich said.
"Furthermore," Froehlich continued, "given the continued use of psychotropic medications in very young children and concerns regarding their effects on the developing brain, future studies on the long-term effects of psychotropic medication use in this age group are essential."