Neuropsychiatric Symptoms of Epilepsy

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D.W. Dunn and W.G. Kronenberger
Approximately 60–70 % of children with epilepsy and ADHD respond to methylphenidate.
This may be less than seen in children with ADHD alone, though none
of the above studies directly compared children with epilepsy and ADHD to children
with ADHD alone. Conflicting data is present in the two studies that had groups
with epilepsy and ADHD and ADHD alone. Semrud-Clikeman and Wical [ 52 ] compared
the response of children with complex partial seizures and ADHD and children
with ADHD alone to methylphenidate as measured by a computerized
performance task. Both groups improved but the children with ADHD alone had
normal scores after methylphenidate whereas the children with epilepsy and ADHD
improved but remained 1.5 standard deviations below normal. Bechtel et al. [ 55 ]
compared the response to methylphenidate of 17 boys with epilepsy and ADHD and
15 boys with ADHD alone. Both groups improved to near-normal scores.
Decisions on second choice medication to use for ADHD and epilepsy if stimulants
are not effective or cause adverse effects are difficult. Atomoxetine, a norepinephrine
reuptake inhibitor, is the next choice in ADHD treatment algorithms. It
does not seem to lower seizure threshold. Wernicke et al. [ 108 ] reviewed company
databases and postmarketing reports and noted rates of 0.1–0.2 % for seizures during
trials of atomoxetine for ADHD and reports of seizures in 8/100,000 drug exposures
after atomoxetine was approved for use. There was no statistically significant
difference in occurrence of seizures in patients receiving atomoxetine, methylphenidate,
or placebo. Torres et al. [ 109 ] reported a retrospective review of 27 patients
with epilepsy that received atomoxetine. Atomoxetine was discontinued in 63 %,
7/17 for inadequate improvement in ADHD symptoms and 9/17 with adverse effects.
There was no worsening in seizure control. In an abstract, Hernández and Barragán
[ 110 ] reported on atomoxetine in 17 children with epilepsy and ADHD, noting
improvement in symptoms of ADHD without an increase in seizure frequency.
Antidepressants and the alpha adrenergics, guanfacine and clonidine, are alternative
agents, but should be used cautiously if at all. There is a high relative risk for
seizures at high doses of bupropion and an intermediate risk at moderate or low
doses. The risk of seizures is intermediate at moderate to high doses of tricyclic
antidepressants [ 111 ]. Guanfacine and clonidine may cause sedation and there are
no published reports of use in patients with ADHD and epilepsy. They remain possible
choices if other medications provide inadequate benefits [ 112 ].
For ADHD without epilepsy, behavioral therapies have been demonstrated to be
effective in clinical trials, although their effect size for short-term improvement in
core ADHD symptoms is somewhat lower than the effect size for stimulant medication
treatment [ 113 ]. The most widely used behavior therapy for ADHD is parent
behavior training (PBT), in which parents are taught to apply behavioral principles
such as ignoring, reinforcement, and contingency management to the specific
behavior challenges associated with ADHD (impulsivity, inattention). Behavioral
therapies for ADHD are also often implemented in the school setting, with teachers
providing frequent, specific behavior feedback associated with target behaviors.
Less often, behavior therapy may be delivered in intensive summer camps that
include activities ranging from classroom work to sports, embedded within a strong
system of behavioral goals, monitoring, and interventions [ 113 ].