Stimulants
Stimulant drugs,specifically amphetamines, were
first used to treat psychiatric disorders in the 1930s
for their pronounced effects of CNS stimulation. In
the past, they were used to treat depression and obe-
sity, but those uses are uncommon in current prac-
tice.Dextroamphetamine (Dexedrine) has been widely
abused to produce a high or to remain awake for long
periods. Today the primary use of stimulants is for
attention deficit/hyperactivity disorder (ADHD) in
children and adolescents, residual attention deficit
disorder in adults, and narcolepsy (attacks of un-
wanted but irresistible daytime sleepiness that dis-
rupt the person’s life).
The primary drugs used to treat ADHD are the
CNS stimulants methylphenidate (Ritalin), pemo-
line (Cylert), and dextroamphetamine. Of these drugs,
methylphenidate accounts for 90% of the medication
given to children for ADHD (Maxmen and Ward,
2002). About 10% to 30% of clients with ADHD do not
respond adequately to the stimulant medications and
are considered treatment-resistant. These persons
have been treated with antidepressants. Nortriptyline
(Pamelor) produced the best results: about 76% of the
persons studied reported a positive response. Fluox-
etine and bupropion were not as effective as nor-
triptyline or the stimulant medications (Maxmen
and Ward, 2002).
MECHANISM OF ACTION
Amphetamines and methylphenidate are often termed
indirectly acting amines because they act by causing
release of the neurotransmitters (norepinephrine,
dopamine, and serotonin) from presynaptic nerve
terminals as opposed to having direct agonist effects
on the postsynaptic receptors. They also block the re-
uptake of these neurotransmitters. Methylphenidate
produces milder CNS stimulation than ampheta-
mines; pemoline primarily affects dopamine and,
therefore, has less effect on the sympathetic nervous
system. It was originally thought that the use of
methylphenidate and pemoline to treat ADHD in chil-
dren produced the reverse effect of most stimulants—
a calming or slowing of activity in the brain. However
this is not the case: stimulants do not have a calming
effect on children who do not have ADHD.40 Unit 1 CURRENTTHEORIES ANDPRACTICE
WARNING: Amphetamines
Potential for abuse is high. Administration for
prolonged periods may lead to drug dependence.WARNING: Methylphenidate
Use with caution in emotionally unstable clients,
such as those with alcohol or drug dependence,
because they may increase the dosage on their
own. Chronic abuse can lead to marked tolerance
and psychic dependence.DOSAGE
For the treatment of narcolepsy in adults, both dextro-
amphetamine and methylphenidate are given in di-
vided doses totaling 20 to 200 mg/day. The higher
dosages may be needed because adults with narco-
lepsy develop tolerance to the stimulants and so re-
quire more medication to sustain improvement.
Methylphenidate is now available as Metadate, an
extended-release drug needing only once-a-day dos-
ing. Tolerance is not seen in persons with ADHD.Table 2-7
STIMULANTDRUGS
Generic (Trade) Name DosageMethylphenidate (Ritalin) Adults: 20–200 mg/day, orally, in divided doses
Children: 10–60 mg/day, orally, in 2–4 divided doses
Dextroamphetamine (Dexedrine) Adults: 20–200 mg/day, orally, in divided doses
Children: 5–40 mg/day, orally, in 2 or 3 divided doses
Pemoline (Cylert) Children: 37.5–112.5 mg/day, orally, given once a day in the morningThe dosages used to treat ADHD in children vary
widely depending on the physician; the age, weight,
and behavior of the child; and the tolerance of the fam-
ily for the child’s behavior. Table 2-7 lists the usual
dosage ranges for these stimulants. Arrangements
must be made for the school nurse or another autho-
rized adult to administer the stimulants to the child
at school.SIDE EFFECTS
The most common side effects of stimulants are
anorexia, weight loss, nausea, and irritability. The
client should avoid caffeine, sugar, and chocolate that
may worsen these symptoms. Less common side ef-
fects include dizziness, dry mouth, blurred vision, and