Comparing stimulant effects in youth with ADHD symptoms and epilepsy

To retrospectively examine response to stimulant treatment in patients with epilepsy and ADHD symptoms as predicted by seizure freedom for six months, use of methylphenidate (MPH) versus amphetamine (AMP) preparations, cognitive level, and medical records were searched for patients under the age of 18 with epilepsy and ADHD symptoms treated with MPH or AMP (n=36, age=10.4 ± 3.5; male=67%). "Responders" had a CGI-improvement score of ≤ 2 and did not stop medication because of adverse effects. "Worsened" patients discontinued medication because of agitation/emotional lability. Seizure freedom did not predict treatment response. Lower cognitive level was associated with increased rate of worsening (p=0.048). No patients who were seizure-free at the start of the medication trial experienced an increase in seizures. Of the patients having seizures at the start of trial, one patient on MPH and two patients on AMP had increased seizures during the trial. Seizures returned to baseline frequency or less after stimulant discontinuation or anticonvulsant adjustment. Methylphenidate was associated with a higher response rate, with 12 of 19 given MPH (0.62 ± 0.28 mg/kg/day) compared with 4 of 17 given AMP (0.37 ± 0.26 mg/kg/day) responding (p=0.03). Methylphenidate treatment and higher cognitive level were associated with improved treatment outcome, while seizure freedom had no clear effect. Confidence in these findings is limited by the study's small, open-label, and uncontrolled design.