The use of medication against attention deficit/hyperactivity disorder in Denmark: a drug use study from a patient perspective

Eur J Clin Pharmacol. 2013 Mar;69(3):589-98. doi: 10.1007/s00228-012-1344-0. Epub 2012 Jul 19.


Aim: Our aim was to characterize utilization patterns for drugs used to treat attention deficit/hyperactivity disorder (ADHD) on the level of the individual patient among Danish users, focusing on treatment duration, doses used, and concurrent use of ADHD and non-ADHD drugs.

Methods: Using the Danish Registry of Medicinal Product Statistics, we extracted data on 1,085,099 prescriptions for ADHD drugs issued to a total of 54,024 persons in the study period 1 January 1995 to 30 September 2011. For users in the final year of the study period, we further extracted 315,365 prescriptions for non-ADHD drugs. Drug utilization was characterized using descriptive statistics.

Results: The mean duration of ADHD treatment was highest (3.6-4.2 years) for patients initiating therapy at a young age (age<13). Dropout rate after receiving only one prescription was highest among off-label users (age<6 and age >17). All age categories showed an increase in the average daily dosage of methylphenidate used from 2003 to 2010. Concomitant treatment with methylphenidate and atomoxetine was rare, as only 2 % of methylphenidate treatment overlapped with atomoxetine treatment. Nineteen percent of methylphenidate instant-release treatment overlapped with methylphenidate controlled-release treatment. Users of ADHD drugs across all age categories had an increased use of drugs related to the nervous system, especially antipsychotics [standardized morbidity rate (SMR), 6.4-19.5] and antiepileptics (SMR, 4.0-5.5).

Conclusion: We found certain traits that warrant further investigation: the apparent increase in average daily doses, the low adherence to treatment among off-label users, and the increased use of other psychotropic medication.

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Attention Deficit Disorder with Hyperactivity / diagnosis
  • Attention Deficit Disorder with Hyperactivity / drug therapy*
  • Attention Deficit Disorder with Hyperactivity / psychology
  • Central Nervous System Stimulants / administration & dosage
  • Central Nervous System Stimulants / adverse effects
  • Central Nervous System Stimulants / therapeutic use*
  • Child
  • Child, Preschool
  • Denmark
  • Drug Prescriptions
  • Drug Therapy, Combination
  • Drug Utilization / trends
  • Drug Utilization Review
  • Guideline Adherence
  • Humans
  • Kaplan-Meier Estimate
  • Medication Adherence*
  • Middle Aged
  • Off-Label Use
  • Patient Dropouts
  • Practice Guidelines as Topic
  • Practice Patterns, Physicians' / trends*
  • Registries
  • Time Factors
  • Treatment Outcome
  • Young Adult


  • Central Nervous System Stimulants