To date, there have been relatively few surveys of psychotropic medicine use in individuals with autism. Data were analyzed from three statewide surveys that employed the same questionnaire and survey methodology. The first was done in the Autism Society of North Carolina in 1992–1993 (NC-1, n = 838; Aman et al. 1995); the second was done in the Autism Society of Ohio in 1999 (Ohio, n = 417; Aman et al. 2003), and the third was done again in the Autism Society of North Carolina in 2001 (NC-2, n = 1538; Langworthy-Lam et al. 2002). Response rates ranged from 48%–56%. Longitudinal trends were examined by comparing the NC-1 and NC-2 data, and regional effects were assessed by comparing the NC-2 and Ohio data. There was a very large increase in antidepressant utilization from 1993 to 2001, with significant increases also occurring for antipsychotics, psychostimulants, and alpha-agonists and beta-blockers. Among youths with autism, the use of any psychotropic increased from 30.5% in NC-1 to 45.2% in NC-2. Psychotropic medication patterns were remarkably consistent across North Carolina and Ohio, except that significantly more autism supplements were used in Ohio. We also examined subject and demographic variables across studies and found several robust correlates of psychotropic medication use. Greater age and handicap, and more restrictive placements, were associated with the use of several drug classes. Knowledge of these patterns may help families and medical planners anticipate future needs.