https://dawninfo.samhsa.gov/files/TNDR09ADHDmeds.htm

Excerpts:

Emergency Department Visits Involving ADHD Stimulant Medications

       a.. An estimated 7,873 drug-related emergency department (ED) visits
involved methylphenidate or amphetamine-dextroamphetamine, two medications
used to treat attention-deficit/hyperactivity disorder (ADHD).
       b.. The most frequent reason for these visits was nonmedical use
(48%), followed by adverse reactions associated with medical use (34%),
accidental ingestion (10%), and suicide attempts (8%).
       c.. The rates of ED visits involving methylphenidate or
amphetamine-dextroamphetamine for patients aged 12 to 17 were higher than
the rates for patients aged 18 or older.
       d.. Over two thirds (68%) of the visits involving nonmedical use of
these two drugs also involved another substance, such as alcohol, an illicit
drug, or pharmaceutical.

Recent studies have indicated that as many as 7 percent of children and 4
percent of adults now meet the criteria for a diagnosis of
attention-deficit/hyperactivity disorder (ADHD).1,2,3 As a result, more
prescriptions are being written for the stimulants used to treat ADHD. More
prescriptions will likely lead to increases in medical side effects
associated with the use of these medications and, potentially, greater use
of these drugs for nonmedical purposes as well.4 A recent Food and Drug
Administration (FDA) advisory panel recognized the danger of side effects
for ADHD stimulants and recommended that they carry a warning of an
increased potential for cardiac problems, such as hypertension, cardiac
arrests, and stroke.5 The possibility of medical problems may be exacerbated
by using ADHD stimulant medications improperly or in combination with other
drugs.

The potential for greater access of these medications to persons without a
prescription is supported by research, which has shown that peers are a
common source of ADHD medications.6 Although the potential for diversion has
increased, estimates from the 2003 National Survey on Drug Abuse and Health
(NSDUH) indicate that nonmedical use of ADHD stimulant medications is still
relatively low: 0.3 percent of the population aged 12 or older reported
using such stimulants nonmedically during the past year. However, those aged
18 to 25 had a higher rate of nonmedical use than those who were younger or
older.7 College students, who may use these drugs as study aids because of
their stimulant properties, fall primarily in this 18-to-25 age group.

The Drug Abuse Warning Network (DAWN), which collects data from a national
sample of short-term, general, non-Federal hospitals,8 provides estimates of
drug-related emergency department (ED) visits. The findings presented in
this issue of The DAWN Report are based on ED visits related to two of the
pharmaceuticals commonly used to treat ADHD-methylphenidate and
amphetamine-dextroamphetamine. DAWN includes both generic and branded drugs,
including methylphenidate marketed as Ritalin© and Concerta© and
amphetamine-dextroamphetamine marketed as Adderal©. Based on DAWN data, this
report examines the reasons for the ED visits and the relative frequency of
these ED visits for different age groups. Finally, for the ED visits
involving nonmedical use, DAWN provides the ability to examine the drugs
used along with the ADHD drugs. DAWN, which observes drug-related morbidity
in ED visits, offers a different view of drug use than the NSDUH, which
measures prevalence of nonmedical use in the population at large.

Overview

In 2004, about 106 million ED visits occurred in short-term, general,
non-Federal hospitals in the United States.9 DAWN estimates that about 2
million ED visits in 2004 were drug related, and the ADHD drugs examined in
this report were implicated in about 1 percent of those drug-related visits.
Methylphenidate was involved in an estimated 3,601 ED visits, and
amphetamine-dextroamphetamine was involved in an estimated 4,272 ED visits.

 Table 1. Estimated ED visits, by reason for ED visit and drug Reason for
visit Methylphenidate Amphetamine-
     dextroamphetamine Total
     ED visits % of visits ED visits % of visits ED visits % of visits
     Totala 3,601 100% 4,272 100% 7,873 100%
     Nonmedical use 1,541   43% 2,228   52% 3,769   48%
     Adverse reaction (medical use) 1,322   37% 1,320   31% 2,642   34%
     Accidental ingestion    390   11%    435   10%    825   10%
     Suicide attempt    348   10%    289     7%    637     8%

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