Adolescent stimulant use
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* Daniel Safer
* Julie Magno Zito

Christiane Poulin unfortunately presented confounded and quite misleading findings in her paper on medical and nonmedical stimulant use among adolescents.1 The major confounder is the inclusion in the student survey questionnaire of diet pills along with other stimulants prescribed specifically for behavioural and emotional disorders.

By combining prescribed stimulant diet pills — which are rarely prescribed to minors — with other prescribed stimulants in an anonymous student survey of prescribed and nonprescribed stimulants, the author obtained findings that do not match available data-based and school nurse survey findings on the prevalence of stimulants prescribed for adolescents.2,3 For example, Poulin's finding of a 3:2 male to female ratio of adolescents reporting prescribed stimulant treatment is inconsistent with the customary finding of a 4–5:1 male to female ratio. (The ratio might have been narrowed by female respondents reporting the use of diet pills.) 

A more striking disparity is the nearly 50% increase in the prevalence of stimulant treatment from grade 7 (median age 13 years) to grade 10 (median age 16 years). This finding is totally at odds with all available data,2,3 including that of Poulin and colleagues from a study using triplicate prescription data on controlled substances in the same locale (Nova Scotia) in 1998.3 Indeed, that study showed that student reporting of medical stimulant use was inaccurate (and confounded). The authors reported a male-to-female ratio of more than 4:1 for methylphenidate and dextroamphetamine prescriptions for school-aged youths. Furthermore, they reported that among youths aged 5–19 years, the highest prevalence of stimulant treatment was in youths aged 10–14 years (the age range in which students in grade 7 would be found), indicating that the prevalence in the 15–19 year age group (the age range in which students in grade 10 would be found) was lower.

The present use of nonprescribed amphetamine drugs among adolescents is high (4%–5% of students in grade 12 in the US report monthly use of these compounds) and nonprescribed diet pills are used as much by secondary school students.4 Clearly, misuse of stimulants by youths is a concern and anonymous student surveys are useful to ascertain the rate. However, such inquiries need to be very precisely defined.

**Daniel Safer** Associate Professor Departments of Psychiatry and Pediatrics Johns Hopkins University School of Medicine Baltimore, Md. **Julie Magno Zito** Associate Professor Departments of Pharmacy and Medicine University of Maryland Baltimore, Md.

## References

1.  1. Poulin C. Medical and nonmedical stimulant use among adolescents: from sanctioned to unsanctioned use. CMAJ 2001;165(8):1039-44.
    
    [Abstract/FREE Full Text](http://www.cmaj.ca/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiY21haiI7czo1OiJyZXNpZCI7czoxMDoiMTY1LzgvMTAzOSI7czo0OiJhdG9tIjtzOjIxOiIvY21hai8xNjcvMS8xNS4yLmF0b20iO31zOjg6ImZyYWdtZW50IjtzOjA6IiI7fQ==) 

2.  2. Safer DJ, Zito JM. Pharmacoepidemiology of methylphenidate and other stimulants for the treatment of ADHD. In: Greenhill LL, Osman BB, editors. *Ritalin: theory and practice*. Larchmont (NY): Liebert; 2000. p. 7-26.
    
    

3.  3. Poulin C, Sketris I, Gordon K. Trends in methylphenidate and dextroamphetamine prescribing in Nova Scotia, Canada [abstract]. *Pharmacoepidemiol Drug Saf* 2001;10(1 Suppl):S30.
    
    

4.  4. Johnson LD, O'Malley PM, Bachman JG. *National survey results on drug use from the Monitoring the Future Study, 1975-1998*. Volume 1: Secondary school students. NIH Publication No. 99-4660. Washington (DC): US Department of Health and Human Services; 1999.