Mianserin pharmacokinetics and behavior in hyperkinetic children.

The present study was conducted to derive pediatric mianserin pharmacokinetic parameters, which were compared to those from healthy young adults, and to obtain preliminary information regarding the utility of mianserin for the management of hyperkinesis in children. The sample consisted of six prepubescent children with hyperkinetic behavior disorders who had not responded, or had developed tolerance to, stimulant medication. Mianserin pharmacokinetics were derived from plasma samples obtained over a 36- to 50-hour period following a single oral dose which ranged from 0.28 to 0.72 mg/kg. Children evidenced a significantly faster elimination half-life and a significantly smaller apparent kinetic volume of distribution than did adults, whereas maximum plasma concentration, time to maximum concentration, and apparent oral plasma clearance were similar. Ratings of behavioral deviance were obtained from teachers and parents during placebo and mianserin titration to a maximum dose of 40 mg/day. Although half the children showed some decrease in hyperactivity ratings, the small sample size and high variability of response preclude conclusions regarding the efficacy of mianserin for childhood hyperkinesis. Possible side effects in our sample included akathisia, excitability, insomnia, and migraine-like headache, as well as cardiovascular effects of tachycardia and two instances of minor electrocardiographic change. Our pharmacokinetic findings will be of import should mianserin prove useful for such childhood disorders as depression and/or enuresis.(ABSTRACT TRUNCATED AT 250 WORDS)