from Janet Currie, Mark Stabile, and Lauren E. Jones:

We examine the effects of a policy change in the province of Quebec, Canada which greatly expanded insurance coverage for prescription medications. We show that the change was associated with a sharp increase in the use of Ritalin, a medication commonly prescribed for ADHD, relative to the rest of Canada. We ask whether this increase in medication use was associated with improvements in emotional functioning and short- and long-run academic outcomes among children with ADHD. We find evidence of increases in emotional problems among girls, and reductions in educational attainment among boys. Our results are silent on the effects on optimal use of medication for ADHD, but suggest that expanding medication use can have negative consequences given the average way these drugs are used in the community.