Efficacy and Safety of St. John´s Wort/Valerian Extract Versus Placebo in Children and Adolescents With ADHD

Inclusion Criteria: * DSM-IV Diagnosis of ADHD * Score of ADHDRS-IV-Parent Version ≥24 * Sufficient knowledge of the German language * Written Informed Consent by parents and patients * Ability to swallow study medication * Sexually mature and active adolescents with highly effective methods of birth control: * contraception according to Pearl-Index \< 1 * when use of oral contraceptives, additional methods of contraception (e.g. condoms) are necessary, i.e. double-barrier Exclusion Criteria: * Known hypersensitivity against St. John´s wort or Valerian root or one of the excipients * Known hypersensitivity of the skin when exposed to sunlight * All serious internal diseases, and for this reason: Current intake of the following medication: * Ciclosporin, Tacrolimus, Indinavir and other protease inhibitors in the anti-HIV treatment * Irinotecan and other cytostatics * anticoagulants of the Cumarin-type, Digoxin, Amitriptylin, Nortriptyline * Midazolam, Theophylline or other medication with photosensitive effects * All severe psychiatric diseases except oppositional defiant disorders (according to items 21-28 SNAP-IV) and conduct disorders (according to items 41-45 SNAP-IV), and for this reason current intake of the following medication: antidepressants and other psychotropic medication * Indication for hospitalization * Suicidality (including suicidal thoughts): Score ≥3 in item 10 of MADRS * Pregnancy, lactation * IQ \< 70 * Positive screening for metabolites of illegal drugs in urine * Previous medication with stimulants and/or atomoxetine * Psychotropic co-medication * Placement in an institution on official or judicial ruling * Parallel participation in another clinical trial according to German Drug Law (AMG), or less than 4 weeks ago * Patients requiring a primary medication with methylphenidate during the study period of 8 weeks